Journal ArticleDOI
Effect of Finite Diaphragm Rupture Process on Microshock Tube Flows
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TLDR
In this article, an axisymmetric computational fluid dynamics (CFD) method was employed to simulate the microshock tube flow field with Maxwell's slip velocity and temperature jump boundary conditions, to accommodate the rarefaction effects.Abstract:
The study of flow physics in microshock tubes is of growing importance with the recent development of microscale technology. The flow characteristics in a microshock tube is considerably different from that of the conventional macroshock tube due to the boundary layer effects and high Knudsen number effects. In the present study an axisymmetric computational fluid dynamics (CFD) method was employed to simulate the microshock tube flow field with Maxwell's slip velocity and temperature jump boundary conditions, to accommodate the rarefaction effects. The effects of finite diaphragm rupture process and partial diaphragm rupture on the flow field and the wave propagations were investigated, in detail. The results show that the shock propagation distance attenuates rapidly for a microshock tube compared to a macroshock tube. For microshock tubes, the contact surface comes closer to the shock front compared to the analytical macroshock tube case. Due to the finite diaphragm rupture process the moving shock front will be generated after a certain distance ahead of the diaphragm and get attenuated rapidly as it propagates compared to the sudden rupture case. The shock-contact distance reduces considerably for the finite diaphragm rupture case compared to the sudden diaphragm rupture process. A partially burst diaphragm within a microshock tube initiates a supersonic flow in the vicinity of the diaphragm similar to that of a supersonic nozzle flow. The supersonic flow expansion leads to the formation of oblique shock cells ahead of the diaphragm and significantly attenuates the moving shock propagation speed.read more
Citations
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Journal ArticleDOI
Novel test section for homogeneous nucleation studies in a pulse expansion wave tube: experimental verification and gasdynamic 2D numerical model
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Insights into the shockwave attenuation in miniature shock tubes
TL;DR: In this paper, the authors presented an experimental analysis of 2mm, 6mm, and 10mm square cross-sections operated at diaphragm rupture pressure ratios in the range 5-25 and driven section initially at ambient conditions.
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Active Flow Control of Supersonic Jet Using Streamwise Pulsed Blowing
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A Parametric Study on the Fluid Dynamics and Performance Characteristic of Micronozzle Flows
TL;DR: In this paper, the fluid dynamics and performance characteristics in micronozzle flows with changes in various geometric parameters using Navier-Stokes simulation based on slip wall boundary conditions were investigated.
References
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Journal ArticleDOI
Micro Flows: Fundamentals and Simulation
TL;DR: In this paper, the authors present a simulation of the transition and free-molecular regime of pressure-driven liquid flow in a shear-driven and separated liquid flow model.
Journal ArticleDOI
Test time in low pressure shock tubes
TL;DR: In this paper, the reduction of test time in low pressure shock tubes, due to a laminar wall boundary layer, has been analytically investigated, and it was found that β is considerably larger than the estimates made by Roshko and Hooker except for very strong shocks.
Journal ArticleDOI
Shock‐Tube Performance at Low Initial Pressure
TL;DR: In this article, an electron beam densitometer has been used to investigate the behavior of a conventional 1⅛in. i.d. shock tube operating at initial pressures of the order of 1 mm Hg.