Thermal modeling of a pulsed plasma rocket engine is a complex and important task, which is performed by highly qualified specialists. Such modeling requires a deep understanding of the processes occurring inside the engine, as well as the ability to use modern methods and tools for calculations and data analysis.

Pulsed plasma rocket engines are one of the most efficient and powerful types of rocket engines used in the space research and commercial industries. These engines work on the basis of using plasma, an ionized gas, as the working substance. Due to this, they have a high level of thrust and are capable of reaching tremendous speeds in outer space.

However, the operation of a pulsed plasma rocket engine is accompanied by high thermal loads, which can negatively affect its performance and durability. Thus, performing thermal modeling is a necessary step in the development and improvement of such engines.

The thermal modeling considers various aspects of pulsed plasma rocket engine operation related to thermal effects on its components. The modeling is based on the heat conduction equations, which allow to determine the distribution of temperatures and heat fluxes inside the engine. This makes it possible to identify hot spots and solve problems related to overheating and damage to materials, as well as to optimize the engine design to improve its thermal performance.

Thermal modeling of a pulsed plasma rocket engine involves the use of specialized software that allows complex calculations and analysis of the thermal behavior of the engine. This involves creating a three-dimensional model of the engine, defining boundary conditions including heat exchange with the environment, and conducting numerical experiments to calculate the heat flux.

The results of thermal modeling not only determine the temperature distribution and heat flow within the engine, but also allow conclusions to be drawn about the efficiency and reliability of the engine. This helps engineers and developers to improve the engine design, optimize the operating processes and improve the overall performance of the engine.

Thus, thermal modeling of pulsed plasma rocket engine is an important tool in the development and improvement of such engines. It identifies problems related to thermal loads and offers solutions for optimizing and improving engine performance. Through careful and accurate thermal modeling, we can improve our rocket engines and ensure successful space missions.

One of the most famous research in the field of pulsed plasma rocket engines is the VASIMR (Variable Specific Impulse Magnetoplasma Rocket) project developed at NASA. This engine uses a magnetic field to heat and ionize the working substance, which makes it possible to achieve high specific impulse thrust. The VASIMR project has potential for use on both low-orbit satellites and interplanetary missions, making it one of the most promising developments to date.

Another example of a successful model of a pulsed plasma rocket engine is the LPT-3 (Large Plasma Thruster — 3rd generation) developed under the European Spacebus program. This engine provides high efficiency and reliability in space, which allows its successful application in commercial satellites. LPT-3 is equipped with a unique modular system that provides flexibility in selecting the required thrust and specific impulse, making it an ideal solution for different missions and operating conditions.

We should not forget about developments in Russia. One significant example of modeling a pulsed plasma rocket engine is the PPA (Plasma Launching Unit) project, which is based on the use of accelerated plasma masses to generate thrust. This makes it possible to achieve high efficiency and increase the specific impulse of the engine. The PSA project has already been successfully tested in the space environment and has shown satisfactory results, indicating the promising potential of this development.

NASA, the European Space Agency and other organizations continue active research and development in this field, which indicates the importance and promise of pulsed plasma rocket motors for future space missions.

The company plans to utilize the grants to model the design of a fully functional PPR, with the objective of determining the availability of necessary materials and power for a rocket propulsion system capable of providing approximately 10 tons of thrust at a specific impulse of more than 5,000 seconds. The PPR is based on the use of a «fuel pellet» made of fissile material (in this case, uranium) that undergoes a transformation into a plasma, which then flows out of the engine and creates thrust. PPR spacecraft are capable of carrying a much smaller volume of working body compared to today’s propulsion systems. However, their design would need to be significantly larger due to the limitations of the plasma creation system in terms of heating.

In 2020, researchers in Phase I of the NIAC program analyzed the chamber in which the fuel pellet is converted into plasma to ascertain its ability to withstand extreme temperatures. To model the trajectories of neutrons and their impact on the rest of the spacecraft, as well as to determine the levels of heat generation in the system, experts from Howe Industries employed the MCNP6 software package, which utilizes the Monte Carlo method.

It is estimated that the plasma should be formed approximately once per second, with each pulse generating energy at a level of approximately 1 kiloelectronvolt. This is considerably less than the energy levels observed in industrial-level nuclear reactors, but high enough for spacecraft propulsion. The energy is converted into heat, with some of it used to eject uranium in the plasma state, creating thrust, while the rest is absorbed by other parts of the system.

Of particular importance in the thermal calculations of the system is the «combustion» chamber. The modeled chamber is made of low-enriched uranium, but with a different isotopic composition than the uranium pellet. This allows the energy released from the fission reaction to be used to heat the chamber itself. Nevertheless, a minor portion of the chamber is composed of highly enriched uranium, which permits the plasma to rapidly disseminate throughout the remainder of the system.

This does not imply that all of the heat generated by the fission reaction will be confined to the chamber. Nevertheless, the author of the final report anticipates that the active cooling system should be sufficient to reduce the temperature to a level where the chamber will not melt. Further research will be conducted to model other components of the system, including the nozzle.

Future testing of these systems will involve the use of prototypes, although the handling of highly enriched uranium does present certain risks. Nevertheless, at this juncture, funding for the second phase of PPR system research under the NIAC program is not yet available. Consequently, it can be surmised that this is still merely a well-designed project and another step in the realization of an idea with a rich history.