Experimental Study on Shock Wave Characteristics in Micro Shock Tube

Recently, the needle-free delivery system has been widely used in medical fields due to its convenience in delivering drug particles into human body without any external needles. In order to penetrate through the outer layer of the skin, drug particles need to obtain enough momentum, which is achieved by accelerating drug particles in a Contoured Shock Tube (CST). The CST consists of a micro shock tube with two diaphragms and an expanded supersonic nozzle. In the present study, experimental studies were carried out by pressure measurement and schlieren visualization. Six high sensitive pressure monitor were used for recording pressure changes as the shock wave moved through different locations along walls in the test section. Different diaphragm pressure ratios were conducted to demonstrate effects of initial diaphragm pressure ratios on shock wave propagation. Shilieren visualization was performed to observe shock wave propagation and shock wave structure in the present experimental shock tube model. The characteristic of the internal flow and shock wave system have been studied and analyzed in details in the present shock tube model.