Amrollah Moradi, Fata Mohammadi Fard, Mahmoud Mani, Mohamadali Ranjbar and Mobin Mottaghipour
In the present research, laboratory shock tube of the Amirkabir University of Technology (AUT) is determined for practical and CFD simulation investigation for moving normal shock wave. The shock tube is geometrically simple and totally axisymmetric. Pressurized gas is produced by a piston compressor stored in a high pressure tank. There are two study cases with the different driver gas pressure and diaphragm thickness. Both driver and driven gas is air. The driven gas part is open to atmosphere. Diaphragms are made of aluminium foil blasting in a certain pressure. There are two pressure sensors in order to capture the moving normal shock wave time intervals. Therefore the speed of moving shock wave is definable. Both cases are considered for CFD simulations. Simulations are done in transient form for laminar viscose flow regime in 2D, axisymmetric geometry. the walls considered to be adiabatic. The time step for simulation is 1e-05 sec which make the case convergent in 20 iterations. The time intervals are very short so the assumptions of adiabatic walls and laminar flow are trustworthy. Map quadrilateral grid employed for domain descritization, so the moving normal shock wave can be captured very well. grid independency study is done for both cases. However the effects of boundary layer and shockwave interaction and wall shear stress are not the goal of present study, but the boundary layer mesh is generated near wall for further studies. Time intervals data for passing shock wave from simulations and engineering calculations show good compatibility with practical data.
