Effect of the stagnation temperature on the normal shock wave

When the stagnation temperature increases, the specific heat does not remain constant and start to vary with this temperature. The gas is perfect, it ’ s state equation remains always valid, except, it was called by gas calorically imperfect or gas at high temperatures. The purpose of this work is to develop a mathematical model for a normal shock wave normal at high temperature when the stagnation temperature is taken into account, less than the dissociation of the molecules as a generalisation model of perfect for constant heat specific. A study on the error given by the perfect gas model compared to our model is presented in order to find a limit of application of the perfect gas model. The application is for air. Keys words : Supersonic flow, subsonic flow, high temperature, supersonic nozzle, thermodynamics ratios, normal shock wave, entropy, relative error, interpolation Nomenclature A cross-section area. a sound velocity. CP specific heat at constant pressure. H enthalpy. M Mach number. P static pressure. R constant of gas. S entropy T temperature. V gas velocity. xP pressure ratio through the shock. xT temperature ratio through the shock. xρ density ration through the shock. ε relative error (%). γ specific heats ratio. ρ density. q mass flow bj coefficients of the polynomial CP(T). K Number of subdivision of the interval * Professor E-mail : [email protected]