Modern developments in the rocket and space technology, as well as the growth in mass and nomenclature of the launched payloads, are making it relevant to use a wide range of both the known and promising fuel pairs in the low-thrust liquid-propellant rocket engines (LPRE). In particular, expansion of the raw material base in the domestic rocket engineering involves using the cryogenic methane as a combustible component for the space and aerospace propulsion systems. On the other hand, the whole world is witnessing the tightening requirements for ecological safety in the spacecraft operation, which also makes the methane use justified. In all the cases, the issue of ensuring satisfactory thermal state of the studied chamber of a low-thrust rocket engine (LTRE) with cooling by its own components stays important, which is fundamentally important for the rocket engines independent operation from the environment. Certain successes achieved in this area are a prerequisite for further researching for approaches to improve the combustion chamber cooling. The computational study objects presented in this article include various modifications of the low-thrust rocket engine chamber operating on the O2gas + + CH4gas fuel components. At the same time, a significant difference from the previously studied samples lies in organization of the axial heat leaks along the combustion chamber (CC) wall. Using computation method for a LTRE chamber with the external regenerative cooling by an oxidizer modified taking into account this fact, design relationships were determined that ensure the structure satisfactory thermal state in the entire range of the parameters alteration. 

 EDN GIDAPV