Numerical Study Of Magnetohydrodynamics Effects On A Supersonic Semispherical Body With An Opposing Jet

Supersonic aircraft is a kind of new aircraft capable of flying at several times thesound velocity. Due to the fact that its high speed could facilitate people’s travel andtransport tremendously and that its realization is an important evaluation of thedevelopment of Aeronautics and Astronautics, it not only has important applicationprospects in Civilian areas, but also is a dispensable part of military realm.However, at present, one of the most important problems that confine theprogress of supersonic aircraft is the enormous drag. Based on the previousexperiments of a spherical body with an opposing jet and the experiments ofmagnetodydrodynamics effect and adopting the finite volume method, this articlesimulated the combined effects of counter-flow and magnetodydrodynamics on dragreduction under supersonic free-stream. Via the combination of the existing dragreduction methods, the simulation provides certain theoretical references for thedesign of aircraft and optimization of aerodynamics force. The current research isillustrated as follows:Firstly, based the previous experiment of a spherical body with an opposing jet, atwo-dimensional axial symmetry spherical body model is established and the propercomputational domain is determined, then is dividing with structured grid. Anumerical simulation is carried out via solving the N-S equations with AUSM,coupled with k-turbulence model. We analyze the effects of the opposing jet on theflow field mode, pressure distribution on body surface and drag. A series of jet exitpressure are employed to analyze the effects of jet exit pressure on drag reductionefficiency. The counter-flow can reduce as much as56%drag coefficient.Secondly, same physical model, computational domain and grid distribution areused to simulate a supersonic spherical body in presence of magnetic field via solvingthe MHD equations with AUSM coupled with k-turbulence model. Themagnetodydrodynamics effects on flow field, pressure distribution and drag areanalyzed. By the application of different electrical conductivity and strength ofmagnetic field, the drag reduction efficiency of magnetodydrodynamics effects isobtained which preliminarily explains the mechanism of magnetodydrodynamicseffects.Lastly, an analysis of the combined effects of counter-flow andmagnetodydrodynamics effects is carried out via analyzing the flow field mode,recirculation zone, reattachment angle and drag coefficient. From comparison, magnetodydrodynamics effects expand the recirculation zone and reattachment angle,therefore, enhance10%drag reduction efficiency.