Reducing the Aerodynamic Drag of the Mating Sections of the Combustion Chambers of Rocket Engines

Annotation: Technological methods for manufacturing cooling elements of modern rocket engines are considered. They are developed taking into account the possibility of reusable use, which reduces the cost of manufacturing similar products. It is shown that in this case, the thermal load on the walls of combustion chambers of liquid rocket engines increases significantly. This required the creation of new ways to protect the surface layer of the hot zone from the thermal effects of the flame in the fuel combustion zone. The possibilities of using plasma application of metal-ceramic heat-protective coatings for these purposes, which have good erosion resistance and high thermal resistance in conditions of intense exposure to high-temperature combustion products, are revealed. The analysis of the influence of the quality of the surface layer of coatings on the performance characteristics of the product is given. As a result, the need for local finishing of the applied coatings is justified, including in the transition areas of the combustion chambers and the jet nozzle, which have limited tool access to the processing zone. Here, the most effective method was the combined alignment of the micro profile with the imposition of an electric field. But for its implementation, a set of studies was needed to study the mechanism of removing the allowance, and to adjust the technological modes. The complex task of minimizing allowances for finishing combined processing was solved, which allowed to align the thickness of the heat-protective coating along the length of the fuel combustion path, including the cleaning sections, to increase the number of trouble-free engine starts by 1.5-2.0 times and ensure reusable use of products.