Numerical Calculation And Analysis Of Aerodynamic Heating Of Aircraft

When the aircraft is flying at a high speed in the atmosphere,strong aerodynamic heating will be caused due to the viscous effect of the gas.The infrared radiation of8 ～ 14mm band mainly comes from the increase of surface temperature of the aircraft caused by aerodynamic heating.Infrared radiation characteristics is related to the survivability and penetration of aircraft in the battlefield.Therefore,the research on the distribution of the temperature field of the aircraft surface caused by aerodynamic heating is of great significance.Based on the basic method of computational fluid dynamics(CFD),in this paper,the distribution of the surface temperature of the aircraft caused by aerodynamic heating was studied and the effects of various factors such as flight velocity,flight height and surface roughness on the surface temperature distribution were analyzed.The main work included the following aspects:(1)The effects of different turbulence models on the numerical results of aerodynamic characteristics were compared to select the turbulence model with high accuracy for calculation of aerodynamic heating.The aerodynamic parameters of NACA 0012 airfoil were calculated with different angles of attack and Mach numbers.Compared with the experimental data,the influences of different turbulence models on the aerodynamic characteristics were studied.The results show that SST k-ω turbulence model is more accurate.SST turbulence model was used to calculate the aerodynamic parameters of the ONERA M6 wing to further verify its accuracy.(2)Based on SST turbulence model,the temperature distributions of the aircraft at different Mach numbers and different heights were calculated and the influences of the flight coditions on the flow field environment and aerodynamic heating were analyzed.The results show that with larger velocity,the shock of the aircraft head is stronger and the shock angle is smaller.As the flight velocity increases and the flight altitude decreases,the aerodynamic heating of the aircrafts becomes more and more serious,and surface temperature increases.(3)Adopting adaptive grid technology,two adaptive methods were used to adaptively encrypt the grid in the flow field according to simulation results.By comparing the results of multiple encrypted grids and unencrypted grids,the effects of adaptive grid on the surface temperature distribution were investigated and the effects of different adaptive methods on numerical results were analyzed respectively.(4)The effects of aircraft surface roughness on aerodynamic heating were studied.The influences on the friction coefficient and the surface temperature distribution of the aircraft were studied by calculating with different surface roughness.The results show that with the increase of surface roughness,the surface friction coefficient of the aircraft is larger and the surface temperature is higher.Moreover,the variation relation of surface temperature and roughness is non-linear.