What place does Russia occupy today, 61 years after the launch of man into space, in terms of space achievements? Against the background of the successes of Elon Musk, it may seem that it is not so significant anymore. However, one unnoticed news of recent days proves the opposite. What are we talking about and what advantages will this give to Russian space satellites?
The dry news sounds like this – Russian scientists intend to complete the development of electrodeless plasma rocket engines (BPRDS) for space exploration by 2024. Several research groups are engaged in the development at once, including the TRINITY Research Center of the Russian Federation, the Keldysh Center and the Kurchatov Institute Research Center. It is planned to create ion and plasma engines of different power, up to 100 kilowatts.
For some reason, such news always goes unnoticed. Chemical rocket engines for launch vehicles are another matter - the roar, the power, a few minutes of work on the way from Earth to space. And plasma rocket engines with their insignificant power are not impressive at all. And in general, it is not entirely clear where they are used and why?
However, for modern spacecraft, spacewalking is only the very beginning of work. Even so, you still have to get to the "place of work" – in the modern world, in order to reduce launch costs, spacecraft are launched in packages, several pieces at a time. Moreover, such packages can reach several dozen satellites.
At the same time, they are not output to the desired point, but to a certain "average" orbit – otherwise, too many required orbits are obtained. Therefore, each vehicle must independently reach the required orbit. And for this, special engines are needed, which work efficiently and for a long time in outer space.
Chemical engines for working in space are suboptimal. Firstly, they consume fuel too quickly, and the mass of fuel and the engine itself is quite large. Secondly, their total working time usually does not exceed tens of minutes. Finally, the use of asymmetric dimethylhydrazine (heptyl) next to delicate electronics requires additional protection, and this again increases the size and weight.
To work in orbit, most spacecraft use electric electrostatic rocket engines, the acceleration of particles of the working fluid in which is carried out in an electrostatic field.
Let's figure it out in order. Rocket engines are all jet engines that use neither energy nor a working fluid from the environment. And an electric rocket engine is an engine whose principle of operation is based on the conversion of electrical energy into directed kinetic energy of particles. Well, a special case of electric motors are electrostatic motors.
Their main principle of operation is to create an electrostatic field, which accelerates the movement of particles of the working fluid, creating kinetic energy. There are two main types of such engines – ion and plasma. Both engines are similar in principle of operation – they use a working fluid (usually based on xenon), the particles of which are accelerated by an electric field or in a quasi-neutral plasma. At the same time, xenon particles gain a very high specific impulse – up to several tens of kilometers per second.
What is the peculiarity of such engines – they very economically consume the working fluid. Their mass, together with the working fluid reserve, ranges from 300 grams to several kilograms. At the same time, they can work hundreds and thousands of hours, unlike chemical engines.
Yes, at the same time they have very little thrust, and on Earth such an engine simply could not be used. But in space, when rapid acceleration is not required, electrostatic motors are very convenient. With their help, you can achieve the desired orbit, provide accurate positioning or even gain speed for long-distance interplanetary missions.
Ion engines cope better with interplanetary flights, they have a much higher specific impulse. And plasma engines work perfectly on spacecraft in Earth orbit. By the way, all OneWeb satellites use plasma engines manufactured by the OKB Fakel – satellites are output in a package, and in order to take their place in orbit, they need to use just such engines.
If plasma engines are already working and in use, then why create new ones? The thing is that the technology of electrostatic rocket engines is constantly being improved. Engines are being created more and more powerful, work is underway to increase efficiency, trouble-free operation time, which has been raised to several thousand hours.
The creation of powerful engines will allow for the movement of spacecraft and a more efficient change of orbit. As Sergey Korobtsev, deputy head of the Kurchatov Institute Research Center complex, says: "By providing long-term cruising in near-Earth space, powerful BPRDS will allow developing space communication and control systems, make it possible to intercept space debris and asteroids, and will allow organizing traffic flows between space objects."
First of all, it is useful for dual-purpose spacecraft. The work of inspection satellites or interceptor satellites can be effective only if the spacecraft has sufficient capabilities to change the orbit, maneuver in space and even change the orbit or information of the enemy spacecraft. For such devices, new engines are simply necessary.
Separately, we can recall the Russian project of the interplanetary nuclear tugboat "Zeus" with a nuclear power plant of the megawatt class. To simplify, the essence of "Zeus" is the presence on board of a nuclear reactor for generating heat, generators for converting thermal energy into electrical energy and a large number of electric electrostatic rocket engines, which are the propellers in this design. The efficiency of the entire system will depend on their power and specific impulse. And this is an opportunity in the future to make multiple flights from Earth's orbit to the Moon and back, the creation of Martian and other interplanetary missions.
And all this is provided by the same ion and plasma engines. As a result, it turns out that behind the seemingly insignificant news there are actually very serious and necessary prospects for the development of Russian cosmonautics. And that Russia not only independently creates and produces such engines for spacecraft, but also constantly improves them and in many ways occupies a leading position in the world.
Mikhail Kotov
