A Supersonic Nozzle Design Using Characteristics Method

The first parameter that is used in the rocket and airplane industries or any other flyingobject is the aerodynamic coefficients and the possibility of aerodynamic design of theflying object. Nozzles are an integral part of most flying bodies. Solving the completeflow equations (Navier-Stokes equations) is difficult and requires big computers, so inmost cases the simplified form of these equations is used. By ignoring the effect of fluidviscosity or the assumption of non-rotating flow, the Navier-Stokes equations areconverted into potential flow equations. One of the methods of solving these equations inthe supersonic flow is the characteristic method. This partial differential equation methodturns into a family of ordinary differential equations, which greatly simplifies the processof solving equations.The method of characteristics is used to solve the supersonic potential flow in a shortlength nozzle and to design a profile that has axial symmetry. The results show that thelength and height of the nozzle increases with the increase of Mach number and throatarea. By increasing the characteristic lines, the accuracy of the solution increases. Byusing this method, it is possible to design an optimal short length nozzle beforemanufacturing.