二次抛物线型面喷管参数的优化选择

二次抛物线型面是火箭发动机喷管较常用的一种型面，对其参数进行优化选择是必要的，在喷管型面长度和出口扩张半角确定的条件下，优化方法是把比冲作为目标函数，利用一维等熵流的气动力公式，二次抛物线型面的几何关系和计算机求极大值方法，确定达到比冲最佳值的设计变量一喷管初扩张角和出口马赫数。

Parameters Optimization of Quadratic Parabola Nozzle Contour

A method of quadratic parabola nozzle contour optimization is presented in the paper. Under the condition of invariable nozzle contour length and exit expansion half angle, the specific impulse is the defined objective function, the nozzle mittal expansion angle and exit Mach number are cosidered as the design variables. Using the one dimensional isoentropic aerodynamic flow formulae, the geometrical relations of quadratiC parabola nozzle contour and the maximization method of computers, the design variables are calculated so that the objective function can be optimized.