Measurements of Shock Wave Attenuation in Ducts with Large Length-to-Diameter Ratios.

摘要

An investigation was conducted to determine the magnitude of viscous attenuation of the shock front in smooth-walled tubes with a length-to-diameter (L/D) ratio of 600. The tests were carried out in a hydrogen driven shock tube of 0.485-inch inside diameter,with air and sulfur hexafluoride as the driven gases. The pressure in the driven section was held at 1atmosphere for the tests ranging up to a Mach number of 8.9. It was reduced below 1atmosphere at higher mach numbers in order to avoid heating. The incident shock produced a square pressure pulse. The initial shock Mach numbers were varied from about 3.5to 15.7. The corresponding initial shock overpressure ratios varied from about 15to 250. (Author)