Influence of High-temperature Air on Three-dimensional Nozzle Structure Design

In this paper, the exit diameter of nozzle is Φ 1.4 m, and the Mach number is 4.0; the nozzle is used in high-speed free jet wind tunnel for engine test with high temperature and pressure air and the mixture of heater combustion as working medium; The mixture is high temperature gas, mainly contains CO2,N2 and H2O. In the process of nozzle structural design, consider the interaction of radiation heat transfer and convection heat transfer fully; heat transfer problems aimed at the nozzle in complex gas, solid, liquid multiphase flow, form the calculation model of the radiation- convection - steady state – convection. Calculated by engineering and Ansys methods, The results show that, the convection heat transfer has an important effect on the air- surface by the high-temperature air in the entrance and the thorat of nozzle; Convection heat has a great influence on the air-surface temperature distribution of nozzle. It must be applied to the solution of temperature field in the nozzle structure design.A great deal of experiments show that, the temperature of the nozzle entrance and exit on the air-surface is close to the calculation results. The experimental results show that the nozzle works very well. In this paper, the calculation is described in details. The teat transfer calculation and some typical experimental results of three-dimensional nozzle and the photographs ofthe nozzle are also presented.