One-Dimensional Interaction between Shock Wave and Low-Porosity Foam. 1st Report. Experiments.

Abstract

Experimental studies on the interaction between a shock wave and a low-porosity foam are conducted by using a shock tube 125 mm in inner diameter and 10080 mm in length. The density of the experimental polyurethane foam is 284 kg/m3. Stress-strain relationships of the foam are investigated experimentally. The purpose is to investigate the effect of the impact of the gas dynamic shock wave on the unsteady deformation of the foam. One end of the foam is fixed to the end wall of the shock tube, and the shock tube flow is initiated by the quick acting valve. Experiments are conducted in the shock tube for incident shock Mach numbers of 1.7 and 1.9. Experimental time histories of the surface stress of the foam at the end of the shock tube show damping vibrations approaching the gas dynamic pressure of the reflected shock wave, and the peak stresses amount to several times the pressure of the reflected shock wave.