Nuclear rocket engine and nuclear propellant. Nuclear rocket engines and nuclear rocket electric propulsion systems

Found an interesting article. In general, nuclear spaceships have always interested me. This is the future of astronautics. Extensive work on this topic was also carried out in the USSR. The article is just about them.

To space on nuclear power. Dreams and reality.

Doctor of Physical and Mathematical Sciences Yu. Ya. Stavissky

In 1950, I defended my diploma as an engineer-physicist at the Moscow Mechanical Institute (MMI) of the Ministry of Ammunition. Five years earlier, in 1945, the Faculty of Engineering and Physics was formed there, training specialists for the new industry, whose tasks mainly included the production of nuclear weapons. The faculty was second to none. Along with fundamental physics in the scope of university courses (methods of mathematical physics, theory of relativity, quantum mechanics, electrodynamics, statistical physics and others), we were taught a full range of engineering disciplines: chemistry, metallurgy, strength of materials, theory of mechanisms and machines, etc. Created by an outstanding Soviet physicist Alexander Ilyich Leypunsky, the Faculty of Engineering and Physics of MMI grew over time into the Moscow Engineering and Physics Institute (MEPhI). Another engineering and physics faculty, which also later merged with MEPhI, was formed at the Moscow Power Engineering Institute (MPEI), but if at MMI the main emphasis was on fundamental physics, then at the Energetic Institute it was on thermal and electrical physics.

We studied quantum mechanics from the book of Dmitry Ivanovich Blokhintsev. Imagine my surprise when, upon assignment, I was sent to work with him. I, an avid experimenter (as a child, I took apart all the clocks in the house), and suddenly I find myself with a famous theorist. I was seized with a slight panic, but upon arrival at the place - “Object B” of the USSR Ministry of Internal Affairs in Obninsk - I immediately realized that I was worrying in vain.

By this time, the main topic of “Object B”, which until June 1950 was actually headed by A.I. Leypunsky, has already formed. Here they created reactors with expanded reproduction of nuclear fuel - “fast breeders”. As director, Blokhintsev initiated the development of a new direction - the creation of nuclear-powered engines for space flights. Mastering space was a long-time dream of Dmitry Ivanovich; even in his youth he corresponded and met with K.E. Tsiolkovsky. I think that understanding the gigantic possibilities of nuclear energy, whose calorific value is millions of times higher than the best chemical fuels, determined the life path of D.I. Blokhintseva.
“You can’t see face to face”... In those years we didn’t understand much. Only now, when the opportunity has finally arisen to compare the deeds and destinies of the outstanding scientists of the Physics and Energy Institute (PEI) - the former “Object B”, renamed on December 31, 1966 - is a correct, as it seems to me, understanding of the ideas that motivated them at that time emerging . With all the variety of activities that the institute had to deal with, it is possible to identify priority scientific areas that were in the sphere of interests of its leading physicists.

The main interest of AIL (as Alexander Ilyich Leypunsky was called behind his back at the institute) is the development of global energy based on fast breeder reactors (nuclear reactors that have no restrictions on nuclear fuel resources). It is difficult to overestimate the importance of this truly “cosmic” problem, to which he devoted the last quarter century of his life. Leypunsky spent a lot of energy on the defense of the country, in particular on the creation of nuclear engines for submarines and heavy aircraft.

Interests D.I. Blokhintsev (he got the nickname “D.I.”) were aimed at solving the problem of using nuclear energy for space flights. Unfortunately, at the end of the 1950s, he was forced to leave this work and lead the creation of an international scientific center - the Joint Institute for Nuclear Research in Dubna. There he worked on pulsed fast reactors - IBR. This became the last big thing of his life.

One goal - one team

DI. Blokhintsev, who taught at Moscow State University in the late 1940s, noticed there and then invited the young physicist Igor Bondarenko, who was literally raving about nuclear-powered spaceships, to work in Obninsk. His first scientific supervisor was A.I. Leypunsky, and Igor, naturally, dealt with his topic - fast breeders.

Under D.I. Blokhintsev, a group of scientists formed around Bondarenko, who united to solve the problems of using atomic energy in space. In addition to Igor Ilyich Bondarenko, the group included: Viktor Yakovlevich Pupko, Edwin Aleksandrovich Stumbur and the author of these lines. The main ideologist was Igor. Edwin conducted experimental studies of ground-based models of nuclear reactors in space installations. I worked mainly on “low thrust” rocket engines (thrust in them is created by a kind of accelerator - “ion propulsion”, which is powered by energy from a space nuclear power plant). We investigated the processes
flowing in ion propulsors, on ground stands.

On Viktor Pupko (in the future
he became the head of the space technology department of the IPPE) there was a lot of organizational work. Igor Ilyich Bondarenko was an outstanding physicist. He had a keen sense of experimentation and carried out simple, elegant and very effective experiments. I think that no experimentalist, and perhaps few theorists, “felt” fundamental physics. Always responsive, open and friendly, Igor was truly the soul of the institute. To this day, the IPPE lives by his ideas. Bondarenko lived an unjustifiably short life. In 1964, at the age of 38, he died tragically due to medical error. It was as if God, seeing how much man had done, decided that it was too much and commanded: “Enough.”

One cannot help but recall another unique personality - Vladimir Aleksandrovich Malykh, a technologist “from God,” a modern Leskovsky Lefty. If the “products” of the above-mentioned scientists were mainly ideas and calculated estimates of their reality, then Malykh’s works always had an output “in metal”. Its technology sector, which at the time of the IPPE's heyday numbered more than two thousand employees, could do, without exaggeration, anything. Moreover, he himself always played the key role.

V.A. Malykh began as a laboratory assistant at the Research Institute of Nuclear Physics of Moscow State University, having completed three courses in physics; the war did not allow him to complete his studies. At the end of the 1940s, he managed to create a technology for the production of technical ceramics based on beryllium oxide, a unique dielectric material with high thermal conductivity. Before Malykh, many struggled unsuccessfully with this problem. And the fuel cell based on commercial stainless steel and natural uranium, developed by him for the first nuclear power plant, is a miracle in those times and even today. Or the thermionic fuel element of the reactor-electric generator created by Malykh to power spacecraft - “garland”. Until now, nothing better has appeared in this area. Malykh’s creations were not demonstration toys, but elements of nuclear technology. They worked for months and years. Vladimir Aleksandrovich became a Doctor of Technical Sciences, laureate of the Lenin Prize, Hero of Socialist Labor. In 1964, he tragically died from the consequences of military shell shock.

Step by step

S.P. Korolev and D.I. Blokhintsev has long nurtured the dream of manned space flight. Close working ties were established between them. But in the early 1950s, at the height of the Cold War, no expense was spared only for military purposes. Rocket technology was considered only as a carrier of nuclear charges, and satellites were not even thought about. Meanwhile, Bondarenko, knowing about the latest achievements of rocket scientists, persistently advocated the creation of an artificial Earth satellite. Subsequently, no one remembered this.

The history of the creation of the rocket that lifted the planet’s first cosmonaut, Yuri Gagarin, into space is interesting. It is connected with the name of Andrei Dmitrievich Sakharov. In the late 1940s, he developed a combined fission-thermonuclear charge, the “puff,” apparently independently of the “father of the hydrogen bomb,” Edward Teller, who proposed a similar product called the “alarm clock.” However, Teller soon realized that a nuclear charge of such a design would have a “limited” power, no more than ~ 500 kilotons equivalent. This is not enough for an “absolute” weapon, so the “alarm clock” was abandoned. In the Union, in 1953, Sakharov’s RDS-6s puff paste was blown up.

After successful tests and Sakharov’s election as an academician, the then head of the Ministry of Medium Machine Building V.A. Malyshev invited him to his place and set him the task of determining the parameters of the next generation bomb. Andrei Dmitrievich estimated (without detailed study) the weight of the new, much more powerful charge. Sakharov’s report formed the basis for a resolution of the CPSU Central Committee and the USSR Council of Ministers, which obliged S.P. Korolev to develop a ballistic launch vehicle for this charge. It was precisely this R-7 rocket called “Vostok” that launched an artificial Earth satellite into orbit in 1957 and a spacecraft with Yuri Gagarin in 1961. There were no plans to use it as a carrier of a heavy nuclear charge, since the development of thermonuclear weapons took a different path.

At the initial stage of the space nuclear program, IPPE, together with Design Bureau V.N. Chelomeya was developing a nuclear cruise missile. This direction did not develop for long and ended with calculations and testing of engine elements created in the department of V.A. Malykha. In essence, we were talking about a low-flying unmanned aircraft with a ramjet nuclear engine and a nuclear warhead (a kind of nuclear analogue of the “buzzing bug” - the German V-1). The system was launched using conventional rocket boosters. After reaching a given speed, thrust was created by atmospheric air, heated by a chain reaction of fission of beryllium oxide impregnated with enriched uranium.

Generally speaking, the ability of a rocket to perform a particular astronautics task is determined by the speed it acquires after using up the entire supply of working fluid (fuel and oxidizer). It is calculated using the Tsiolkovsky formula: V = c×lnMn/ Mk, where c is the exhaust velocity of the working fluid, and Mn and Mk are the initial and final mass of the rocket. In conventional chemical rockets, the exhaust velocity is determined by the temperature in the combustion chamber, the type of fuel and oxidizer, and the molecular weight of the combustion products. For example, the Americans used hydrogen as fuel in the descent module to land astronauts on the Moon. The product of its combustion is water, whose molecular weight is relatively low, and the flow rate is 1.3 times higher than when burning kerosene. This is enough for the descent vehicle with astronauts to reach the surface of the Moon and then return them to the orbit of its artificial satellite. Korolev’s work with hydrogen fuel was suspended due to an accident with human casualties. We did not have time to create a lunar lander for humans.

One of the ways to significantly increase the exhaust rate is to create nuclear thermal rockets. For us, these were ballistic nuclear missiles (BAR) with a range of several thousand kilometers (a joint project of OKB-1 and IPPE), while for the Americans, similar systems of the “Kiwi” type were used. The engines were tested at testing sites near Semipalatinsk and Nevada. The principle of their operation is as follows: hydrogen is heated in a nuclear reactor to high temperatures, passes into the atomic state and in this form flows out of the rocket. In this case, the exhaust speed increases by more than four times compared to a chemical hydrogen rocket. The question was to find out to what temperature hydrogen could be heated in a reactor with solid fuel cells. Calculations gave about 3000°K.

At NII-1, whose scientific director was Mstislav Vsevolodovich Keldysh (then President of the USSR Academy of Sciences), the department of V.M. Ievleva, with the participation of the IPPE, was working on a completely fantastic scheme - a gas-phase reactor in which a chain reaction occurs in a gas mixture of uranium and hydrogen. Hydrogen flows out of such a reactor ten times faster than from a solid fuel reactor, while uranium is separated and remains in the core. One of the ideas involved the use of centrifugal separation, when a hot gas mixture of uranium and hydrogen is “swirled” by incoming cold hydrogen, as a result of which the uranium and hydrogen are separated, as in a centrifuge. Ievlev tried, in fact, to directly reproduce the processes in the combustion chamber of a chemical rocket, using as an energy source not the heat of fuel combustion, but the fission chain reaction. This opened the way to the full use of the energy capacity of atomic nuclei. But the question of the possibility of pure hydrogen (without uranium) flowing out of the reactor remained unresolved, not to mention the technical problems associated with maintaining high-temperature gas mixtures at pressures of hundreds of atmospheres.

IPPE's work on ballistic nuclear missiles ended in 1969-1970 with “fire tests” at the Semipalatinsk test site of a prototype nuclear rocket engine with solid fuel elements. It was created by the IPPE in cooperation with the Voronezh Design Bureau A.D. Konopatov, Moscow Research Institute-1 and a number of other technological groups. The basis of the engine with a thrust of 3.6 tons was the IR-100 nuclear reactor with fuel elements made of a solid solution of uranium carbide and zirconium carbide. The hydrogen temperature reached 3000°K with a reactor power of ~170 MW.

Low thrust nuclear rockets

So far we have been talking about rockets with a thrust exceeding their weight, which could be launched from the surface of the Earth. In such systems, increasing the exhaust velocity makes it possible to reduce the supply of working fluid, increase the payload, and eliminate multi-stage operation. However, there are ways to achieve practically unlimited outflow velocities, for example, acceleration of matter by electromagnetic fields. I worked in this area in close contact with Igor Bondarenko for almost 15 years.

The acceleration of a rocket with an electric propulsion engine (EPE) is determined by the ratio of the specific power of the space nuclear power plant (SNPP) installed on them to the exhaust velocity. In the foreseeable future, the specific power of the KNPP, apparently, will not exceed 1 kW/kg. In this case, it is possible to create rockets with low thrust, tens and hundreds of times less than the weight of the rocket, and with very low consumption of the working fluid. Such a rocket can only launch from the orbit of an artificial Earth satellite and, slowly accelerating, reach high speeds.

For flights within the Solar System, rockets with an exhaust speed of 50-500 km/s are needed, and for flights to the stars, “photon rockets” that go beyond our imagination with an exhaust speed equal to the speed of light. In order to carry out a long-distance space flight of any reasonable time, unimaginable power density of power plants is required. It is not yet possible to even imagine what physical processes they could be based on.

Calculations have shown that during the Great Confrontation, when the Earth and Mars are closest to each other, it is possible to fly a nuclear spacecraft with a crew to Mars in one year and return it to the orbit of an artificial Earth satellite. The total weight of such a ship is about 5 tons (including the supply of the working fluid - cesium, equal to 1.6 tons). It is determined mainly by the mass of the KNPP with a power of 5 MW, and the jet thrust is determined by a two-megawatt beam of cesium ions with an energy of 7 kiloelectronvolts *. The ship launches from the orbit of an artificial Earth satellite, enters the orbit of a Mars satellite, and will have to descend to its surface on a device with a hydrogen chemical engine, similar to the American lunar one.

A large series of IPPE works was devoted to this area, based on technical solutions that are already possible today.

Ion propulsion

In those years, ways of creating various electric propulsion systems for spacecraft, such as “plasma guns”, electrostatic accelerators of “dust” or liquid droplets were discussed. However, none of the ideas had a clear physical basis. The discovery was surface ionization of cesium.

Back in the 20s of the last century, American physicist Irving Langmuir discovered the surface ionization of alkali metals. When a cesium atom evaporates from the surface of a metal (in our case, tungsten), whose electron work function is greater than the cesium ionization potential, in almost 100% of cases it loses a weakly bound electron and turns out to be a singly charged ion. Thus, the surface ionization of cesium on tungsten is the physical process that makes it possible to create an ion propulsion device with almost 100% utilization of the working fluid and with an energy efficiency close to unity.

Our colleague Stal Yakovlevich Lebedev played a major role in creating models of an ion propulsion system of this type. With his iron tenacity and perseverance, he overcame all obstacles. As a result, it was possible to reproduce a flat three-electrode ion propulsion circuit in metal. The first electrode is a tungsten plate measuring approximately 10x10 cm with a potential of +7 kV, the second is a tungsten grid with a potential of -3 kV, and the third is a thoriated tungsten grid with zero potential. The “molecular gun” produced a beam of cesium vapor, which, through all the grids, fell on the surface of the tungsten plate. A balanced and calibrated metal plate, the so-called balance, served to measure the “force,” i.e., the thrust of the ion beam.

The accelerating voltage to the first grid accelerates cesium ions to 10,000 eV, the decelerating voltage to the second grid slows them down to 7000 eV. This is the energy with which the ions must leave the thruster, which corresponds to an exhaust speed of 100 km/s. But a beam of ions, limited by the space charge, cannot “go into outer space.” The volumetric charge of the ions must be compensated by electrons to form a quasi-neutral plasma, which spreads unhindered in space and creates reactive thrust. The source of electrons to compensate for the volume charge of the ion beam is the third grid (cathode) heated by current. The second, “blocking” grid prevents electrons from getting from the cathode to the tungsten plate.

The first experience with the ion propulsion model marked the beginning of more than ten years of work. One of the latest models, with a porous tungsten emitter, created in 1965, produced a “thrust” of about 20 g at an ion beam current of 20 A, had an energy utilization rate of about 90% and matter utilization of 95%.

Direct conversion of nuclear heat into electricity

Ways to directly convert nuclear fission energy into electrical energy have not yet been found. We still cannot do without an intermediate link - a heat engine. Since its efficiency is always less than one, the “waste” heat needs to be put somewhere. There are no problems with this on land, in water or in the air. In space, there is only one way - thermal radiation. Thus, KNPP cannot do without a “refrigerator-emitter”. The radiation density is proportional to the fourth power of absolute temperature, so the temperature of the radiating refrigerator should be as high as possible. Then it will be possible to reduce the area of ​​the radiating surface and, accordingly, the mass of the power plant. We came up with the idea of ​​using “direct” conversion of nuclear heat into electricity, without a turbine or generator, which seemed more reliable for long-term operation at high temperatures.

From the literature we knew about the works of A.F. Ioffe - the founder of the Soviet school of technical physics, a pioneer in the research of semiconductors in the USSR. Few people now remember the current sources he developed, which were used during the Great Patriotic War. At that time, more than one partisan detachment had contact with the mainland thanks to “kerosene” TEGs - Ioffe thermoelectric generators. A “crown” made of TEGs (it was a set of semiconductor elements) was put on a kerosene lamp, and its wires were connected to radio equipment. The “hot” ends of the elements were heated by the flame of a kerosene lamp, the “cold” ends were cooled in air. The heat flow, passing through the semiconductor, generated an electromotive force, which was enough for a communication session, and in the intervals between them the TEG charged the battery. When, ten years after the Victory, we visited the Moscow TEG plant, it turned out that they were still being sold. Many villagers then had economical Rodina radios with direct-heat lamps, powered by a battery. TAGs were often used instead.

The problem with kerosene TEG is its low efficiency (only about 3.5%) and low maximum temperature (350°K). But the simplicity and reliability of these devices attracted developers. Thus, semiconductor converters developed by the group of I.G. Gverdtsiteli at the Sukhumi Institute of Physics and Technology, found application in space installations of the Buk type.

At one time A.F. Ioffe proposed another thermionic converter - a diode in a vacuum. The principle of its operation is as follows: the heated cathode emits electrons, some of them, overcoming the potential of the anode, do work. Much higher efficiency (20-25%) was expected from this device at operating temperatures above 1000°K. In addition, unlike a semiconductor, a vacuum diode is not afraid of neutron radiation, and it can be combined with a nuclear reactor. However, it turned out that it was impossible to implement the idea of ​​a “vacuum” Ioffe converter. As in an ion propulsion device, in a vacuum converter you need to get rid of the space charge, but this time not ions, but electrons. A.F. Ioffe intended to use micron gaps between the cathode and anode in a vacuum converter, which is practically impossible under conditions of high temperatures and thermal deformations. This is where cesium comes in handy: one cesium ion produced by surface ionization at the cathode compensates for the space charge of about 500 electrons! In essence, a cesium converter is a “reversed” ion propulsion device. The physical processes in them are close.

“Garlands” by V.A. Malykha

One of the results of IPPE's work on thermionic converters was the creation of V.A. Malykh and serial production in his department of fuel elements from series-connected thermionic converters - “garlands” for the Topaz reactor. They provided up to 30 V - a hundred times more than single-element converters created by “competing organizations” - the Leningrad group M.B. Barabash and later - the Institute of Atomic Energy. This made it possible to “remove” tens and hundreds of times more power from the reactor. However, the reliability of the system, stuffed with thousands of thermionic elements, raised concerns. At the same time, steam and gas turbine plants operated without failures, so we also paid attention to the “machine” conversion of nuclear heat into electricity.

The whole difficulty lay in the resource, because in long-distance space flights, turbogenerators must operate for a year, two, or even several years. To reduce wear, the “revolutions” (turbine rotation speed) should be made as low as possible. On the other hand, a turbine operates efficiently if the speed of the gas or steam molecules is close to the speed of its blades. Therefore, first we considered the use of the heaviest - mercury steam. But we were frightened by the intense radiation-stimulated corrosion of iron and stainless steel that occurred in a mercury-cooled nuclear reactor. In two weeks, corrosion “ate” the fuel elements of the experimental fast reactor “Clementine” at the Argonne Laboratory (USA, 1949) and the BR-2 reactor at the IPPE (USSR, Obninsk, 1956).

Potassium vapor turned out to be tempting. The reactor with potassium boiling in it formed the basis of the power plant we were developing for a low-thrust spacecraft - potassium steam rotated the turbogenerator. This “machine” method of converting heat into electricity made it possible to count on an efficiency of up to 40%, while real thermionic installations provided an efficiency of only about 7%. However, KNPP with “machine” conversion of nuclear heat into electricity was not developed. The matter ended with the release of a detailed report, essentially a “physical note” to the technical design of a low-thrust spacecraft for a crewed flight to Mars. The project itself was never developed.

Later, I think, interest in space flights using nuclear rocket engines simply disappeared. After the death of Sergei Pavlovich Korolev, support for IPPE’s work on ion propulsion and “machine” nuclear power plants noticeably weakened. OKB-1 was headed by Valentin Petrovich Glushko, who had no interest in bold, promising projects. The Energia Design Bureau, which he created, built powerful chemical rockets and the Buran spacecraft returning to Earth.

"Buk" and "Topaz" on the satellites of the "Cosmos" series

Work on the creation of KNPP with direct conversion of heat into electricity, now as power sources for powerful radio satellites (space radar stations and television broadcasters), continued until the start of perestroika. From 1970 to 1988, about 30 radar satellites were launched into space with Buk nuclear power plants with semiconductor converter reactors and two with Topaz thermionic plants. The Buk, in fact, was a TEG - a semiconductor Ioffe converter, but instead of a kerosene lamp it used a nuclear reactor. It was a fast reactor with a power of up to 100 kW. The full load of highly enriched uranium was about 30 kg. Heat from the core was transferred by liquid metal - a eutectic alloy of sodium and potassium - to semiconductor batteries. Electric power reached 5 kW.

The Buk installation, under the scientific guidance of the IPPE, was developed by OKB-670 specialists M.M. Bondaryuk, later - NPO "Red Star" (chief designer - G.M. Gryaznov). The Dnepropetrovsk Yuzhmash Design Bureau (chief designer - M.K. Yangel) was tasked with creating a launch vehicle to launch the satellite into orbit.

The operating time of “Buk” is 1-3 months. If the installation failed, the satellite was transferred to a long-term orbit at an altitude of 1000 km. Over almost 20 years of launches, there were three cases of a satellite falling to Earth: two in the ocean and one on land, in Canada, in the vicinity of Great Slave Lake. Kosmos-954, launched on January 24, 1978, fell there. He worked for 3.5 months. The satellite's uranium elements burned completely in the atmosphere. Only the remains of a beryllium reflector and semiconductor batteries were found on the ground. (All this data is presented in the joint report of the US and Canadian atomic commissions on Operation Morning Light.)

The Topaz thermionic nuclear power plant used a thermal reactor with a power of up to 150 kW. The full load of uranium was about 12 kg - significantly less than that of the Buk. The basis of the reactor were fuel elements - “garlands”, developed and manufactured by Malykh’s group. They consisted of a chain of thermoelements: the cathode was a “thimble” made of tungsten or molybdenum, filled with uranium oxide, the anode was a thin-walled tube of niobium, cooled by liquid sodium-potassium. The cathode temperature reached 1650°C. The electrical power of the installation reached 10 kW.

The first flight model, the Cosmos-1818 satellite with the Topaz installation, entered orbit on February 2, 1987 and operated flawlessly for six months until cesium reserves were exhausted. The second satellite, Cosmos-1876, was launched a year later. He worked in orbit almost twice as long. The main developer of Topaz was the MMZ Soyuz Design Bureau, headed by S.K. Tumansky (former design bureau of aircraft engine designer A.A. Mikulin).

This was in the late 1950s, when we were working on ion propulsion, and he was working on the third stage engine for a rocket that would fly around the Moon and land on it. Memories of Melnikov’s laboratory are still fresh to this day. It was located in Podlipki (now the city of Korolev), on site No. 3 of OKB-1. A huge workshop with an area of ​​about 3000 m2, lined with dozens of desks with daisy chain oscilloscopes recording on 100 mm roll paper (this was a bygone era; today one personal computer would be enough). At the front wall of the workshop there is a stand where the combustion chamber of the “lunar” rocket engine is mounted. Oscilloscopes have thousands of wires from sensors for gas velocity, pressure, temperature and other parameters. The day begins at 9.00 with the ignition of the engine. It runs for several minutes, then immediately after stopping, a team of first-shift mechanics disassembles it, carefully inspects and measures the combustion chamber. At the same time, oscilloscope tapes are analyzed and recommendations for design changes are made. Second shift - designers and workshop workers make recommended changes. During the third shift, a new combustion chamber and diagnostic system are installed at the stand. A day later, at exactly 9.00 am, the next session. And so on without days off for weeks, months. More than 300 engine options per year!

This is how chemical rocket engines were created, which had to work for only 20-30 minutes. What can we say about testing and modifications of nuclear power plants - the calculation was that they should work for more than one year. This required truly gigantic efforts.

Often in general educational publications about astronautics, they do not distinguish the difference between a nuclear rocket engine (NRE) and a nuclear electric propulsion system (NURE). However, these abbreviations hide not only the difference in the principles of converting nuclear energy into rocket thrust, but also a very dramatic history of the development of astronautics.

The drama of history lies in the fact that if research on nuclear propulsion and nuclear propulsion in both the USSR and the USA, which had been stopped mainly for economic reasons, had continued, then human flights to Mars would have long ago become commonplace.

It all started with atmospheric aircraft with a ramjet nuclear engine

The engines developed as part of the Pluto project were planned to be installed on cruise missiles, which in the 1950s were created under the designation SLAM (Supersonic Low Altitude Missile, supersonic low-altitude missile).

The United States planned to build a rocket 26.8 meters long, three meters in diameter, and weighing 28 tons. The rocket body was supposed to contain a nuclear warhead, as well as a nuclear propulsion system having a length of 1.6 meters and a diameter of 1.5 meters. Compared to other sizes, the installation looked very compact, which explains its direct-flow principle of operation.

The developers believed that, thanks to the nuclear engine, the SLAM missile's flight range would be at least 182 thousand kilometers.

In 1964, the US Department of Defense closed the project. The official reason was that in flight, a nuclear-powered cruise missile pollutes everything around too much. But in fact, the reason was the significant costs of maintaining such rockets, especially since by that time rocketry was rapidly developing based on liquid-propellant rocket engines, the maintenance of which was much cheaper.

The USSR remained faithful to the idea of ​​​​creating a ramjet design for a nuclear powered engine much longer than the United States, closing the project only in 1985. But the results turned out to be much more significant. Thus, the first and only Soviet nuclear rocket engine was developed at the Khimavtomatika design bureau, Voronezh. This is RD-0410 (GRAU Index - 11B91, also known as “Irbit” and “IR-100”).

The RD-0410 used a heterogeneous thermal neutron reactor, the moderator was zirconium hydride, the neutron reflectors were made of beryllium, the nuclear fuel was a material based on uranium and tungsten carbides, with about 80% enrichment in the 235 isotope.

The design included 37 fuel assemblies, covered with thermal insulation that separated them from the moderator. The project provided that the hydrogen flow first passed through the reflector and moderator, maintaining their temperature at room temperature, and then entered the core, where it cooled the fuel assemblies, heating up to 3100 K. At the stand, the reflector and moderator were cooled by a separate hydrogen flow.

The reactor went through a significant series of tests, but was never tested for its full operating duration. However, the outside reactor components were completely exhausted.

Technical characteristics of RD 0410

Thrust in void: 3.59 tf (35.2 kN)
Reactor thermal power: 196 MW
Specific thrust impulse in vacuum: 910 kgf s/kg (8927 m/s)
Number of starts: 10
Working resource: 1 hour
Fuel components: working fluid - liquid hydrogen, auxiliary substance - heptane
Weight with radiation protection: 2 tons
Engine dimensions: height 3.5 m, diameter 1.6 m.

Relatively small overall dimensions and weight, high temperature of nuclear fuel (3100 K) with an effective cooling system with a hydrogen flow indicate that the RD0410 is an almost ideal prototype of a nuclear propulsion engine for modern cruise missiles. And, taking into account modern technologies for producing self-stopping nuclear fuel, increasing the resource from an hour to several hours is a very real task.

Nuclear rocket engine designs

There are three types of nuclear propulsion engines depending on the type of fuel for the reactor:

• solid phase;
• liquid phase;
• gas phase.

In gas-phase nuclear propellant engines, the fuel (for example, uranium) and the working fluid are in a gaseous state (in the form of plasma) and are held in the working area by an electromagnetic field. Uranium plasma heated to tens of thousands of degrees transfers heat to the working fluid (for example, hydrogen), which, in turn, being heated to high temperatures forms a jet stream.

Based on the type of nuclear reaction, a distinction is made between a radioisotope rocket engine, a thermonuclear rocket engine and a nuclear engine itself (the energy of nuclear fission is used).

An interesting option is also a pulsed nuclear rocket engine - it is proposed to use a nuclear charge as a source of energy (fuel). Such installations can be of internal and external types.

The main advantages of nuclear powered engines are:

• high specific impulse;
• significant energy reserves;
• compactness of the propulsion system;
• the possibility of obtaining very high thrust - tens, hundreds and thousands of tons in a vacuum.

• fluxes of penetrating radiation (gamma radiation, neutrons) during nuclear reactions;
• removal of highly radioactive compounds of uranium and its alloys;
• outflow of radioactive gases with the working fluid.

Nuclear propulsion system

For example, the outstanding Russian scientist Anatoly Sazonovich Koroteev, the author of the invention under the patent, provided a technical solution for the composition of equipment for a modern YARDU. Below I present part of the said patent document verbatim and without comment.

The essence of the proposed technical solution is illustrated by the diagram presented in the drawing. A nuclear propulsion system operating in propulsion-energy mode contains an electric propulsion system (EPS) (the example diagram shows two electric rocket engines 1 and 2 with corresponding feed systems 3 and 4), a reactor installation 5, a turbine 6, a compressor 7, a generator 8, heat exchanger-recuperator 9, Ranck-Hilsch vortex tube 10, refrigerator-radiator 11. In this case, turbine 6, compressor 7 and generator 8 are combined into a single unit - a turbogenerator-compressor. The nuclear propulsion unit is equipped with pipelines 12 of the working fluid and electrical lines 13 connecting the generator 8 and the electric propulsion unit. The heat exchanger-recuperator 9 has the so-called high-temperature 14 and low-temperature 15 working fluid inputs, as well as high-temperature 16 and low-temperature 17 working fluid outputs.

The output of the reactor unit 5 is connected to the input of turbine 6, the output of turbine 6 is connected to the high-temperature input 14 of the heat exchanger-recuperator 9. The low-temperature output 15 of the heat exchanger-recuperator 9 is connected to the entrance to the Ranck-Hilsch vortex tube 10. The Ranck-Hilsch vortex tube 10 has two outputs , one of which (via the “hot” working fluid) is connected to the radiator refrigerator 11, and the other (via the “cold” working fluid) is connected to the input of the compressor 7. The output of the radiator refrigerator 11 is also connected to the input to the compressor 7. Compressor output 7 is connected to the low-temperature 15 input to the heat exchanger-recuperator 9. The high-temperature output 16 of the heat exchanger-recuperator 9 is connected to the input to the reactor installation 5. Thus, the main elements of the nuclear power plant are interconnected by a single circuit of the working fluid.

The nuclear power plant works as follows. The working fluid heated in the reactor installation 5 is sent to the turbine 6, which ensures the operation of the compressor 7 and the generator 8 of the turbogenerator-compressor. Generator 8 generates electrical energy, which is sent through electrical lines 13 to electric rocket engines 1 and 2 and their supply systems 3 and 4, ensuring their operation. After leaving the turbine 6, the working fluid is sent through the high-temperature inlet 14 to the heat exchanger-recuperator 9, where the working fluid is partially cooled.

Then, from the low-temperature outlet 17 of the heat exchanger-recuperator 9, the working fluid is directed into the Ranque-Hilsch vortex tube 10, inside which the working fluid flow is divided into “hot” and “cold” components. The “hot” part of the working fluid then goes to the refrigerator-emitter 11, where this part of the working fluid is effectively cooled. The “cold” part of the working fluid goes to the inlet of the compressor 7, and after cooling, the part of the working fluid leaving the radiating refrigerator 11 also follows there.

Compressor 7 supplies the cooled working fluid to the heat exchanger-recuperator 9 through the low-temperature inlet 15. This cooled working fluid in the heat exchanger-recuperator 9 provides partial cooling of the counter flow of the working fluid entering the heat exchanger-recuperator 9 from the turbine 6 through the high-temperature inlet 14. Next, the partially heated working fluid (due to heat exchange with the counter flow of the working fluid from the turbine 6) from the heat exchanger-recuperator 9 through the high-temperature outlet 16 again enters the reactor installation 5, the cycle is repeated again.

Thus, a single working fluid located in a closed loop ensures continuous operation of the nuclear power plant, and the use of a Ranque-Hilsch vortex tube as part of the nuclear power plant in accordance with the claimed technical solution improves the weight and size characteristics of the nuclear power plant, increases the reliability of its operation, simplifies its design and makes it possible to increase efficiency of nuclear power plants in general.

Valery Lebedev (review)

• In history, there have already been developments of cruise missiles with a ramjet nuclear air engine: this is the SLAM rocket (aka Pluto) in the USA with the TORY-II reactor (1959), the Avro Z-59 concept in the UK, developments in the USSR.
• Let's touch on the principle of operation of a rocket with a nuclear reactor. We are only talking about a ramjet nuclear engine, which was precisely what Putin had in mind in his speech about a cruise missile with an unlimited flight range and complete invulnerability. The atmospheric air in this rocket is heated by the nuclear assembly to high temperatures and is ejected from the rear nozzle at high speed. Tested in Russia (in the 60s) and among the Americans (since 1959). It has two significant drawbacks: 1. It stinks like the same nuclear bomb, so during the flight everything on the trajectory will be clogged. 2. In the thermal range it stinks so much that even a North Korean satellite with radio tubes can see it from space. Accordingly, you can knock down such a flying kerosene stove with complete confidence.
  So the cartoons shown in the Manege led to bewilderment, which grew into concern about the (mental) health of the director of this garbage.
  In Soviet times, such pictures (posters and other pleasures for generals) were called “Cheburashkas”.

  In general, this is a conventional straight-through design, axisymmetric with a streamlined central body and shell. The shape of the central body is such that, due to shock waves at the inlet, the air is compressed (the operating cycle starts at a speed of 1 M and higher, to which it is accelerated by a starting accelerator using conventional solid fuel);
  - inside the central body there is a nuclear heat source with a monolithic core;
  - the central body is connected to the shell by 12-16 plate radiators, where heat is removed from the core by heat pipes. The radiators are located in the expansion zone in front of the nozzle;
  - material of radiators and central body, for example, VNDS-1, which maintains structural strength up to 3500 K in the limit;
  - to be sure, we heat it up to 3250 K. The air, flowing around the radiators, heats up and cools them. It then passes through the nozzle, creating thrust;
  - to cool the shell to acceptable temperatures, we build an ejector around it, which at the same time increases thrust by 30-50%.

  An encapsulated monolithic nuclear power plant unit can either be installed in the housing before launch, or kept in a subcritical state until launch, and the nuclear reaction can be started if necessary. I don’t know how exactly, this is an engineering problem (and therefore amenable to solution). So this is clearly a weapon of the first strike, don’t go to grandma.
  An encapsulated nuclear power plant unit can be made in such a way that it is guaranteed not to be destroyed upon impact in the event of an accident. Yes, it will turn out to be heavy - but it will turn out to be heavy in any case.

  To reach hypersound, you will need to allocate a completely indecent energy density per unit time to the working fluid. With a 9/10 probability, existing materials will not be able to handle this over long periods of time (hours/days/weeks), the rate of degradation will be insane.

  And in general, the environment there will be aggressive. Protection from radiation is heavy, otherwise all the sensors/electronics can be thrown into a landfill at once (those interested can remember Fukushima and the questions: “why weren’t robots given the job of cleaning?”).

  Etc.... Such a prodigy will “glow” significantly. It is not clear how to transmit control commands to it (if everything is completely screened there).

  Let's touch on authentically created missiles with a nuclear power plant - an American design - the SLAM missile with the TORY-II reactor (1959).

  Here is this engine with a reactor:

  The SLAM concept was a three-mach low-flying rocket of impressive dimensions and weight (27 tons, 20+ tons after the launch boosters were jettisoned). The terribly expensive low-flying supersonic made it possible to make maximum use of the presence of a practically unlimited source of energy on board; in addition, an important feature of a nuclear air jet engine is the improvement of operating efficiency (thermodynamic cycle) with increasing speed, i.e. the same idea, but at speeds of 1000 km/h it would have a much heavier and larger engine. Finally, 3M at an altitude of a hundred meters in 1965 meant invulnerability to air defense.

  

  Engine TORY-IIC. The fuel elements in the active zone are hexagonal hollow tubes made of UO2, covered with a protective ceramic shell, assembled in incalo fuel assemblies.

  It turns out that previously the concept of a Cruise Missile with a nuclear power plant was “tied up” at high speed, where the advantages of the concept were strong, and competitors with hydrocarbon fuel were weakening.

• Video about the old American SLAM rocket

• The missile shown at Putin’s presentation is transonic or subsonic (if, of course, you believe that it is the one in the video). But at the same time, the size of the reactor decreased significantly compared to TORY-II from the SLAM rocket, where it was as much as 2 meters including the radial neutron reflector made of graphite.
  Diagram of the SLAM rocket. All drives are pneumatic, the control equipment is located in a radiation-attenuating capsule.

  Is it even possible to install a reactor with a diameter of 0.4-0.6 meters? Let's start with a fundamentally minimal reactor - a Pu239 pig. A good example of the implementation of such a concept is the Kilopower space reactor, which, however, uses U235. The diameter of the reactor core is only 11 centimeters! If we switch to plutonium 239, the size of the core will drop by another 1.5-2 times.
  Now from the minimum size we will begin to step towards a real nuclear air jet engine, remembering the difficulties. The very first thing to add to the size of the reactor is the size of the reflector - in particular, in Kilopower BeO triples the size. Secondly, we cannot use U or Pu blanks - they will simply burn out in the air flow in just a minute. A shell is needed, for example from incaloy, which resists instant oxidation up to 1000 C, or other nickel alloys with a possible ceramic coating. The introduction of a large amount of shell material into the core increases the required amount of nuclear fuel several times at once - after all, the “unproductive” absorption of neutrons in the core has now increased sharply!
  Moreover, the metal form of U or Pu is no longer suitable - these materials themselves are not refractory (plutonium generally melts at 634 C), and they also interact with the material of the metal shells. We convert the fuel into the classical form of UO2 or PuO2 - we get another dilution of the material in the core, this time with oxygen.

  Finally, let's remember the purpose of the reactor. We need to pump a lot of air through it, to which we will give off heat. approximately 2/3 of the space will be occupied by “air tubes”. As a result, the minimum diameter of the core grows to 40-50 cm (for uranium), and the diameter of the reactor with a 10-centimeter beryllium reflector to 60-70 cm.

  An airborne nuclear jet engine can be shoved into a rocket with a diameter of about a meter, which, however, is still not radically larger than the stated 0.6-0.74 m, but is still alarming.

  One way or another, the nuclear power plant will have a power of ~several megawatts, powered by ~10^16 decays per second. This means that the reactor itself will create a radiation field of several tens of thousands of roentgens at the surface, and up to a thousand roentgens along the entire rocket. Even installing several hundred kg of sector protection will not significantly reduce these levels, because Neutron and gamma rays will be reflected from the air and “bypass the protection.” In a few hours, such a reactor will produce ~10^21-10^22 atoms of fission products with an activity of several (several tens) petabecquerels, which even after shutdown will create a background of several thousand roentgens near the reactor. The rocket design will be activated to about 10^14 Bq, although the isotopes will be primarily beta emitters and are only dangerous by bremsstrahlung X-rays. The background from the structure itself can reach tens of roentgens at a distance of 10 meters from the rocket body.

  All these difficulties give the idea that the development and testing of such a missile is a task on the verge of the possible. It is necessary to create a whole set of radiation-resistant navigation and control equipment, to test it all in a fairly comprehensive way (radiation, temperature, vibration - and all this for statistics). Flight tests with a working reactor can at any moment turn into a radiation disaster with a release of hundreds of terrabecquerels to several petabecquerels. Even without catastrophic situations, depressurization of individual fuel elements and the release of radionuclides are very likely.
  Because of all these difficulties, the Americans abandoned the SLAM nuclear-powered rocket in 1964.

  Of course, in Russia there is still the Novaya Zemlya test site where such tests can be carried out, but this will contradict the spirit of the treaty banning nuclear weapons tests in three environments (the ban was introduced to prevent systematic pollution of the atmosphere and ocean with radionuclides).

  Finally, I wonder who in the Russian Federation could develop such a reactor. Traditionally, the Kurchatov Institute (general design and calculations), Obninsk IPPE (experimental testing and fuel), and the Luch Research Institute in Podolsk (fuel and materials technology) were initially involved in high-temperature reactors. Later, the NIKIET team became involved in the design of such machines (for example, the IGR and IVG reactors are prototypes of the core of the RD-0410 nuclear rocket engine). Today NIKIET has a team of designers who carry out work on the design of reactors (high-temperature gas-cooled RUGK, fast reactors MBIR), and IPPE and Luch continue to engage in related calculations and technologies, respectively. In recent decades, the Kurchatov Institute has moved more toward the theory of nuclear reactors.

  To summarize, we can say that the creation of a cruise missile with air jet engines with a nuclear power plant is generally a feasible task, but at the same time extremely expensive and complex, requiring a significant mobilization of human and financial resources, it seems to me to a greater extent than all other announced projects (" Sarmat", "Dagger", "Status-6", "Vanguard"). It is very strange that this mobilization did not leave the slightest trace. And most importantly, it is completely unclear what the benefits of obtaining such types of weapons (against the background of existing carriers) are, and how they can outweigh the numerous disadvantages - issues of radiation safety, high cost, incompatibility with strategic arms reduction treaties.

  The small-sized reactor has been developed since 2010, Kiriyenko reported about this in the State Duma. It was assumed that it would be installed on a spacecraft with an electric propulsion system for flights to the Moon and Mars and tested in orbit this year.
  Obviously, a similar device is used for cruise missiles and submarines.

  Yes, it is possible to install a nuclear engine, and successful 5-minute tests of a 500 megawatt engine, made in the states many years ago for a cruise missile with a ram jet for a speed of Mach 3, in general, confirmed this (Project Pluto). Bench tests, of course (the engine was “blown” with prepared air of the required pressure/temperature). But why? Existing (and projected) ballistic missiles are sufficient for nuclear parity. Why create a weapon that is potentially more dangerous (for “our own people”) to use (and test)? Even in the Pluto project it was implied that such a missile flies over its territory at a considerable altitude, descending to sub-radar altitudes only close to enemy territory. It's not very good to be next to an unprotected 500 megawatt air-cooled uranium reactor with materials temperatures over 1300 Celsius. True, the mentioned rockets (if they are really being developed) will be less powerful than Pluto (Slam).
  Animation video from 2007, issued in Putin’s presentation for showing the latest cruise missile with a nuclear power plant.
  
  Perhaps all this is preparation for the North Korean version of blackmail. We will stop developing our dangerous weapons - and you will lift sanctions from us.
  What a week - the Chinese boss is pushing for lifelong rule, the Russian one is threatening the whole world.

Russia has tested the cooling system of a nuclear power plant (NPP), one of the key elements of a future spacecraft that will be able to carry out interplanetary flights. Why is a nuclear engine needed in space, how does it work and why Roscosmos considers this development to be the main Russian space trump card, Izvestia reports.

History of the atom

If you put your hand on your heart, since the time of Korolev, the launch vehicles used for flights into space have not undergone any fundamental changes. The general principle of operation - chemical, based on the combustion of fuel with an oxidizer - remains the same. Engines, control systems, and types of fuel are changing. The basis of space travel remains the same - jet thrust pushes the rocket or spacecraft forward.

It is very common to hear that a major breakthrough is needed, a development that can replace the jet engine in order to increase efficiency and make flights to the Moon and Mars more realistic. The fact is that at present, almost the majority of the mass of interplanetary spacecraft is fuel and oxidizer. What if we abandon the chemical engine altogether and start using the energy of a nuclear engine?

The idea of ​​creating a nuclear propulsion system is not new. In the USSR, a detailed government decree on the problem of creating nuclear propulsion systems was signed back in 1958. Even then, studies were carried out that showed that, using a nuclear rocket engine of sufficient power, you can get to Pluto (which has not yet lost its planetary status) and back in six months (two there and four back), spending 75 tons of fuel on the trip.

The USSR was developing a nuclear rocket engine, but scientists have only now begun to approach a real prototype. It's not about money, the topic turned out to be so complex that not a single country has yet been able to create a working prototype, and in most cases it all ended with plans and drawings. The United States tested a propulsion system for a flight to Mars in January 1965. But the NERVA project to conquer Mars using a nuclear engine did not move beyond the KIWI tests, and it was much simpler than the current Russian development. China has set in its space development plans the creation of a nuclear engine closer to 2045, which is also very, very not soon.

In Russia, a new round of work on the megawatt-class nuclear electric propulsion system (NPP) project for space transport systems began in 2010. The project is being created jointly by Roscosmos and Rosatom, and it can be called one of the most serious and ambitious space projects of recent times. The lead contractor for nuclear power engineering is the Research Center named after. M.V. Keldysh.

Nuclear movement

Throughout development, news leaks to the press about the readiness of one or another part of the future nuclear engine. At the same time, in general, except for specialists, few people imagine how and due to what it will work. Actually, the essence of a space nuclear engine is approximately the same as on Earth. The energy of the nuclear reaction is used to heat and operate the turbogenerator-compressor. To put it simply, a nuclear reaction is used to produce electricity, almost exactly the same as in a conventional nuclear power plant. And with the help of electricity, electric rocket engines operate. In this installation, these are high-power ion engines.

In ion engines, thrust is created by creating jet thrust based on ionized gas accelerated to high speeds in an electric field. Ion engines still exist and are being tested in space. So far they have only one problem - almost all of them have very little thrust, although they consume very little fuel. For space travel, such engines are an excellent option, especially if the problem of generating electricity in space is solved, which is what a nuclear installation will do. In addition, ion engines can operate for quite a long time; the maximum period of continuous operation of the most modern models of ion engines is more than three years.

If you look at the diagram, you will notice that nuclear energy does not begin its useful work immediately. First, the heat exchanger heats up, then electricity is generated, which is already used to create thrust for the ion engine. Alas, humanity has not yet learned how to use nuclear installations for propulsion in a simpler and more efficient way.

In the USSR, satellites with a nuclear installation were launched as part of the Legend target designation complex for naval missile-carrying aircraft, but these were very small reactors, and their work was only enough to generate electricity for the instruments hung on the satellite. Soviet spacecraft had an installation power of three kilowatts, but now Russian specialists are working on creating an installation with a power of more than a megawatt.

Problems on a cosmic scale

Naturally, a nuclear installation in space has many more problems than on Earth, and the most important of them is cooling. Under normal conditions, water is used for this, which absorbs engine heat very effectively. This cannot be done in space, and nuclear engines require an effective cooling system - and the heat from them must be removed into outer space, that is, this can only be done in the form of radiation. Typically, for this purpose, spacecraft use panel radiators - made of metal, with coolant fluid circulating through them. Alas, such radiators, as a rule, have a large weight and dimensions, in addition, they are in no way protected from meteorites.

In August 2015, at the MAKS air show, a model of drop cooling of nuclear power propulsion systems was shown. In it, liquid dispersed in the form of drops flies in open space, cools, and then reassembles into the installation. Just imagine a huge spaceship, in the center of which is a giant shower installation, from which billions of microscopic drops of water burst out, fly through space, and then are sucked into the huge mouth of a space vacuum cleaner.

More recently, it became known that the droplet cooling system of a nuclear propulsion system was tested under terrestrial conditions. At the same time, the cooling system is the most important stage in creating the installation.

Now it’s a matter of testing its performance in zero-gravity conditions, and only after that can we try to create a cooling system in the dimensions required for installation. Each such successful test brings Russian specialists a little closer to the creation of a nuclear installation. Scientists are rushing with all their might, because it is believed that launching a nuclear engine into space will help Russia regain its leadership position in space.

Nuclear space age

Let’s say this succeeds, and in a few years a nuclear engine will begin operating in space. How will this help, how can it be used? To begin with, it is worth clarifying that in the form in which the nuclear propulsion system exists today, it can only operate in outer space. There is no way it can take off from the Earth and land in this form; for now it cannot do without traditional chemical rockets.

Why in space? Well, humanity flies to Mars and the Moon quickly, and that’s all? Not certainly in that way. Currently, all projects of orbital plants and factories operating in Earth orbit are stalled due to lack of raw materials for work. There is no point in building anything in space until a way is found to put large quantities of the required raw materials, such as metal ore, into orbit.

But why lift them from Earth if, on the contrary, you can bring them from space. In the same asteroid belt in the solar system there are simply huge reserves of various metals, including precious ones. And in this case, the creation of a nuclear tug will simply be a lifesaver.

Bring a huge platinum- or gold-bearing asteroid into orbit and start cutting it apart right in space. According to experts, such production, taking into account the volume, may turn out to be one of the most profitable.

Is there a less fantastic use for a nuclear tug? For example, it can be used to transport satellites in the required orbits or bring spacecraft to the desired point in space, for example, to lunar orbit. Currently, upper stages are used for this, for example the Russian Fregat. They are expensive, complex and disposable. A nuclear tug will be able to pick them up in low Earth orbit and deliver them wherever needed.

The same goes for interplanetary travel. Without a quick way to deliver cargo and people into Mars orbit, there is simply no chance of colonization. The current generation of launch vehicles will do this very expensively and for a long time. Until now, flight duration remains one of the most serious problems when flying to other planets. Surviving months of travel to Mars and back in a closed spacecraft capsule is no easy task. A nuclear tug can help here too, significantly reducing this time.

Necessary and sufficient

At present, all this looks like science fiction, but, according to scientists, there are only a few years left before testing the prototype. The main thing that is required is not only to complete the development, but also to maintain the required level of astronautics in the country. Even with a drop in funding, rockets must continue to take off, spacecraft are built, and the most valuable specialists must continue to work.

Otherwise, one nuclear engine without the appropriate infrastructure will not help the matter; for maximum efficiency, the development will be very important not only to sell, but to use independently, showing all the capabilities of the new space vehicle.

In the meantime, all residents of the country who are not tied to work can only look at the sky and hope that everything will work out for the Russian cosmonautics. And a nuclear tug, and the preservation of current capabilities. I don’t want to believe in other outcomes.

A rocket engine in which the working fluid is either a substance (for example, hydrogen) heated by the energy released during a nuclear reaction or radioactive decay, or directly the products of these reactions. Distinguish... ... Big Encyclopedic Dictionary

A rocket engine in which the working fluid is either a substance (for example, hydrogen) heated by the energy released during a nuclear reaction or radioactive decay, or directly the products of these reactions. Is in… … encyclopedic Dictionary

nuclear rocket engine- branduolinis raketinis variklis statusas T sritis Gynyba apibrėžtis Raketinis variklis, kuriame reaktyvinė trauka sudaroma vykstant branduolinei arba termobranduolinei reakcijai. Branduoliniams raketiniams varikliams sudaroma kur kas didesnė… … Artilerijos terminų žodynas

- (Nuclear Jet) a rocket engine in which thrust is created due to the energy released during radioactive decay or a nuclear reaction. According to the type of nuclear reaction occurring in the nuclear engine, a radioisotope rocket engine is distinguished... ...

- (YRD) rocket engine, in which the source of energy is nuclear fuel. In a nuclear powered engine with a nuclear reactor. The torus heat released as a result of a nuclear chain reaction is transferred to the working fluid (for example, hydrogen). Nuclear reactor core... ...

This article should be Wikified. Please format it according to the article formatting rules. Nuclear rocket engine using a homogeneous solution of nuclear fuel salts (English... Wikipedia

Nuclear rocket engine (NRE) is a type of rocket engine that uses the energy of fission or fusion of nuclei to create jet thrust. They are actually reactive (heating the working fluid in a nuclear reactor and releasing gas through... ... Wikipedia

A jet engine, the energy source and working fluid of which is located in the vehicle itself. The rocket engine is the only one practically mastered for launching a payload into orbit of an artificial Earth satellite and for use in ... ... Wikipedia

- (RD) A jet engine that uses for its operation only substances and energy sources available in reserve on a moving vehicle (aircraft, ground, underwater). Thus, unlike air-jet engines (See... ... Great Soviet Encyclopedia

Isotopic rocket engine, a nuclear rocket engine that uses the decay energy of radioactive chemical isotopes. elements. This energy serves to heat the working fluid, or the working fluid is the decomposition products themselves, forming... ... Big Encyclopedic Polytechnic Dictionary