Passive Control of Impulsive Wave Discharged from Open-End of Tube : Reduction of Magnitude by Means of Box with Helical Vane

Abstract

When the propagating shock wave reaches at the exit portal of a tube, the impulsive wave discharges to the surrounding area. A new method of passive control that weakens the magnitude of impulsive wave is proposed in this study. An experiment study using a simple shock tube was carried out to examine the effects of a box/helical-vane system at the open-end of a tube. The effect of this system on reduction of the magnitude of impulsive wave is compared with other method of the passive control. The results show that the magnitude of impulsive wave could be significantly reduced by the new method of passive control using the box/helical-vane system. The optimal size of box and helical-vane regarding to decrease of the impulsive wave are determined also.