The effect of molecular relaxation processes in air on the rise time of sonic boomsA theory is developed to explain the effect of molecular relaxation processes on the rise time of sonic booms. To determine the rise time of sonic booms, both O2 and N2 relaxation processes must be included. The N2 relaxation process delays the shock pressure reaching the maximum pressure, and the O2 relaxation process causes a shock profile to have a gentle slope. The N2 relaxation controls the lower part of overpressure; the O2 relaxation controls the higher part. The constant rise time curves show that the rise times increase as the overpressures and humidity decrease. The present approach gives longer rise times than those acquired by Bass et al. for given shock overpressures.
Document ID
19920063259
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Kang, Jongmin (NASA Langley Research Center Hampton, VA, United States)
Pierce, Allan D. (Pennsylvania State University University Park, United States)
Date Acquired
August 15, 2013
Publication Date
January 1, 1990
Subject Category
Fluid Mechanics And Heat Transfer
Meeting Information
Meeting: International Congress on Recent Developments in Air and Structure-Borne Sound and Vibration