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We continue the description of a lowMach number hydrodynamics algorithm for reacting, full star flows. Here we demonstrate how to accurately incorporate reactions using a second-order accurate Strang-splitting technique. We also improve the fidelity of the model by allowing the base state to evolve in response to large-scale convection as well as large-scale heating, taking care to account for ...

We present the results of an experimental investigation conducted as part of a multidisciplinary effort intended to address systematically the problem of closed-loop flow control by assembling expertise from numerical and experimental flow analysis, flow modeling, and control design disciplines. Experiments were conducted using a shallow-cavity flow in a small-scale wind tunnel that can operate...

A hybrid simulation model with kinetic ions, massless fluid electrons, and phenomenological resistivity is used to study the perpendicular configuration of the bow shocks of the earth and other planets. We investigate a wide range of parameters, including the upstream Mach number, electron and ion beta (ratios of thermal to magnetic pressure), and resistivity. Electron beta and resistivity are ...

An experimental study was conducted to investigate the physics underlying the oscillation cycle of high Mach number, turbulent, open cavity flows. The specific aim was to investigate how the interaction between the cavity acoustics and the shear layer dynamics is affected by increasing Mach number. In the experiments the free-stream Mach numbers tested were 2 and 5, the cavity length-to-depth r...

Direct numerical simulation (DNS) is used to study laminar to turbulent transition induced by a discrete hemispherical roughness element in a high-speed laminar boundary layer. The simulations are performed under conditions matching the experiments of Danehy et al. (AIAA Paper 2009–394, 2009) for free-stream Mach numbers of 3.37, 5.26 and 8.23. It is observed that the Mach 8.23 flow remains lam...

Shock waves generated at different parts of vehicle interact with the boundary layer over the surface at high Mach flows. The adverse pressure gradient across strong shock wave causes the flow to separate and peak loads are generated at separation and reattachment points. The size of separation bubble in the shock boundary layer interaction flows depends on various parameters. Reynolds-averaged...

The convective period leading up to a Type Ia supernova (SN Ia) explosion is characterized by very low Mach number flows, requiring hydrodynamic methods well-suited to long-time integration. We continue the development of the lowMach number equation set for stellar-scale flows by incorporating the effects of heat release due to external sources. Low Mach number hydrodynamics equations with a ti...

SUMMARY Results are repvted of tests on a two-dimensional combined external/internal compressIon Intake having a design Mach number of 2.2. The particular parameters investigated in the tests now reported are:-(a) sidewall bleed, (b) a 3 to 1 range of free stream Reynolds number, (cl the length of subsonic diffuser, Cd) sidewalls out back to the line of the second ramp shock. The maximum pressu...