It is important to investigate a pressure profile when a diffracted shock wave interacts with a reflector from a safety point of view. Because the diffracted shock waves are often generated by the explosions of combustible gases to cause serious damages against a human body and surrounding buildings. Therefore, maximum pressure behind the reflected shock wave is the most important parameter and this report is concerned with the evaluation of maximum pressure, which is the function of Mach number of the shock wave, the distance from a source of the shock tube, initial pressure of the gas, and diameter of the shock wave, etc. In this study, a detonation-driven shock tube of 14 m long and 50 mm diameter is used to generate a strong shock wave of propagating Mach number 3.0 ≤ Ms ≤ 5.2. The shock wave is diffracted from an open end of the shock tube of 25 mm diameter and reflected from a cylindrical reflector of 50 mm diameter. These phenomena are observed using color-schlieren optical techniques and the pressure histories at the stagnation point of the reflector are simultaneously measured. As a result, (ⅰ) The behavior on the diffracted shock wave and complicate flow-fields behind the shock wave are observed, (ⅱ) An empirical equation to estimate the maximum pressure behind reflected shock wave is obtained by the results of experimental and numerical simulation with the aid of dimensional analysis.
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