基于Lagrange液膜方法的小推力液体火箭发动机耦合传热策略研究

To research cooling effects of the film formed by small thrust liquid rocket engine’s border nozzle, a coupling heat transfer method which considers the combustion flowing, gas radiation, liquid film cooling, structure heat transfer and radiation cooling was proposed, then a series of liquid film calculating model using Lagrange method were set up. A 490N liquid rocket engine was simulated using this coupling heat transfer method. The results show that the largest film’s thickness is 60μm. The longest liquid film’s length is 30mm. The temperature of the wall covered by liquid film is limited to about 420K, so the liquid film has an expected cooling effect. The film formed by the smaller angle of the injection panel is compacter with the longer survival time, which prevents the central heat transfer to the structure effectively. The larger angel film has a greater circumferential range, which relieves the heat transfer from the structure to the head.