Magnetic control of flow past a blunt body: Numerical validation and exploration

Abstract

Computational and theoretical studies of a Mach 5 flow over a hemisphere were carried out to validate a new computer code for magnetogasdynamic simulation, and to examine the possibility of heat transfer mitigation through magnetic control. Sample calculations were made using a local solution developed by W. B. Bush [J. Aerosp. Sci. 25, 685 (1958); 28, 610 (1961)] for the stagnation point flow over an axisymmetric blunt body with an imposed dipole magnetic field. Numerical computations, which obviated many of the simplifications inherent in the Bush theory, were carried out employing the low magnetic Reynolds number approximation. Both models indicate that an imposed dipole field can slow the flow in the conductive shock layer and consequently reduce the wall heat flux in the vicinity of the stagnation point. The theoretical model predicts a slightly higher level of heat transfer than that obtained computationally, but there is good agreement between the two models in the fractional change in heat transfer with increasing strength of the applied magnetic field. For both models, nonuniform electrical conductivity was found to reduce the effectiveness of a given applied field. Magnetic flow control is seen to have a sound physical basis, and may prove to be a useful technology for heat transfer mitigation.

Radiative Aerothermodynamics of Entering Space Vehicles: Toward the Use of State-to-State Approach

“…31b) fields at Mach number M∞ = 3.05 using an electrical conductivity σ = 4.9x10 5 (Ωm) -1 . Results reveal that the magnetic field effectively pushes the bow shock wave further away from the blunt-body as already observed by different authors [91,92,95]. For this case, the shock envelope in the plasma field exhibits an outward displacement compared to the gas dynamic shock by a factor 2 in stand-off distance Δ (see Fig.…”

“…Up to now, only few works using upwind methods with a self-consistent, finite and non-homogeneous electrical conductivity have been afforded [88][89][90][91][92]. For this reason, in this work we have developed a two-dimensional MHD model describing a chemically reacting nitrogen hypersonic flow past a bluntbody.…”

Magnetic Field Effects on Axis-Switching and Instabilities in Rectangular Plasma Jets

“…For flow control applications, Rm can be in the range of 1 to 10 while Re can be of order 10 4 [20,21]. Within propulsion devices, Rm can vary several orders of magnitude.…”

“…Based on the report of [20,21], it is preferable to perform MHD-RJ studies with Rm ∼ 5 and Re ∼ 10 4 .While computations with Rm ∼ 5 is straight-forward, direct simulations of turbulent jets of Re ∼ 10 4 require substantial computational resources. Based on the findings of non-MHD jets [9], we suggest that crucial physical insight into turbulent rectangular jet structures and instabilities can be obtained at much smaller transitional Reynolds numbers.…”

Control of Aerodynamic Characteristics of Lifting Reentry Vehicle with Applied Magnetic Field

“…The thermochemical nonequilibrium effects are considered using Park's two-temperature model and Park's chemical reaction model 6,7) . In this numerical simulation, the electromagnetic effects are included as a source term 8) . The governing equation is expressed as follows;…”