Experimental and numerical simulation to study the two-dimensional effects due to area contraction near the diaphragm of a shock tube

• Main Authors: Amir A.-F., Yusoff M.Z., Shuaib N.H.
• Other Authors: 15750212500
• Format: Article
• Published: 2023
• Subjects: CFD; Shock tube; Shock tunnel; Shock wave; Diaphragms; Mach number; Shock tubes; Test facilities; Transducers; Tunnels; Two dimensional; Waves; Actual experiments; Area-changes; CFD simulations; Diaphragm pressure; Effective area; Euler solver; Experimental data; Experimental measurements; Experimental procedure; Experimental test; Flow process; Flow regions; Flow speed; High precision; High speed flows; Malaysia; Numerical formulation; Numerical simulation; On flow; Operating condition; Pressure history; Recirculating flow; Rupture process; Time-accurate; Tube diameters; Two parameter; Two-dimensional effects; Wave strengths; Wedge angle; Tubes (components)
• Institution: Universiti Tenaga Nasional

The aim of this paper is to develop a numerical formulation and an experimental procedure to investigate the effects of area change on flow conditions in shock tube. Two dimensional time accurate Euler solver for shock tube applications was developed to simulate the flow process inside the shock tube. The solver was developed based on the dimensions of a newly built short-duration high speed flow test facility at Universiti Tenaga Nasional "UNITEN" in Malaysia. The facility has been designed, built, and commissioned for different values of diaphragm pressure ratios P 4/P 1 in order to get wide range of Mach number. A bush with diameter less than tube diameter is used to facilitate the rupture process. In the actual experiment, the effective area of the diaphragm (throat) opening at rupture will be some what smaller than the bush opening area. There will be also a dead flow region (recirculating flow) downstream of the bush. The exact location of the reattachment point will be highly dependent on the flow speed. In the present work, since the two parameters are not known, the effective throat area and the wedge angle were calibrated and the values which give the closest agreement between experimental data and CFD simulation results were used. Experimental tests for different operating conditions have been conducted. High precision pressure transducers were used to get the pressure history which represents the shock wave strength P 2/P 1. The agreements obtained between CFD results and experimental measurements have been reasonable. � 2009 WASET.ORG.