Gas Film/Regenerative Composite Cooling Characteristics of the Lox/Lch4 Rocket Engine

The thermal protection of rocket engines is a key focus in rocket engine design. Therefore, the gas film/ regenerative composite cooling of the LOX/LCH4 rocket engine thrust chamber was studied herein. Based on the Tribus classical gas film cooling efficiency formula, the gas film cooling model was established, and in combination with the one-dimensional regenerative cooling model, the gas film/regenerative composite cooling model was established. The key parameters of heat transfer performance were also calculated. The results showed that: Firstly, compared with regenerative cooling, the composite cooling performance was significantly improved. A higher gas film flow rate led to a higher cooling efficiency and a lower gas-side wall temperature. Secondly, the introduction position of the film greatly influenced the cooling performance. The introduction position of the gas film was optimized when it was introduced from a single-row of holes, which made the wall temperature distribution more uniform and lowered the peak value. Thirdly, compared with a single-row of holes, a double-row of holes can enhance the cooling effect of the gas film superposition area and further reduce the gas-side wall temperature in this area. These results can provide a basis for the design of gas film/regenerative composite cooling systems.