Design and performance investigations on UAV’s convergent-divergent nozzle through validated computational aerodynamic simulation

Nowadays, the researcher works on the advancement in aerospace sector in developing towards safety, exceeding sonic speed or breaking sound barriers, etc. This work discuss about the performance of the UAV’s [Unmanned Aerial Vehicle] nozzle, especially interested to investigate in speed near the sonic it is one of the complicated flow regimes. From area velocity relation for achieving speeds greater than Mach one, the system needs the combination of convergent and divergent section joining at the throat where maximum mass flow rate achieved. In this work compare the numerical simulation result and experimental result of flow through C-D nozzle which is designed by varying major nozzle design parameter like chamber pressure, ambient pressure, nozzle expansion area ratio, nozzle shape and exit angle. The conceptual designs of various C-D nozzles are modeled through CATIA. The main objective of this work is to investigate the characteristics of C-D nozzle by comparatively studying the numerical simulation for three different inlet pressures and by experimentally investigating on the high speed lab facilities. By varying the pressure at different values, the shock wave patterns are studied and compared. The experimental investigation is done by using the Shadowgraph technique and the numerical simulation is performed by using the ANSYS Fluent. Exit Mach number for different inlet pressures (4, 5 and 6 bar) is obtained from simulation results and compared with theoretical exit Mach number values and error percentage are calculated.