Publication

Abstract :

Transient numerical analysis has been carried out by simulating the fluid flow over sharp, conical, blunt, hemispherical, and aerodisk spiked cylinders. They have been subjected to hypersonic flow of Mach number 6.1, at zero angle of attack, so as to investigate the variations of frequency and thus the Strouhal number during hypersonic buzz phenomenon at various L/D ratios by capturing the flow unsteadiness using Ansys Fluent solver. It has been concluded that the frequency of hypersonic buzz is maximum at a particular L/D ratio known as the critical L/D ratio, which is unique for each type of spike. Above the critical L/D ratio, the buzz frequency decreases almost linearly with an increase in the L/D ratio, and below the critical L/D ratio, the frequency decreases drastically with a reduction in L/D, and finally the hypersonic buzz ceases to occur below a certain L/D ratio for every type of spiked body. Analysis of the aerodisk spiked cylinder revealed no hypersonic buzz phenomenon for any practical L/D ratios. Further, the correspondence between CD and pressure history at the probe point has also been verified. © 2018 by Begell House, Inc.