磁流体动力学在高超声速飞行器应用中的几个基本问题

Recently, it has become the highlight in the aeronautical and astronautical field worldwide that how magnetohydrodynamics is applied to hypersonic aircrafts. Currently, research on magnetofluid technology mainly concentrates on the following four aspects: engine design based on magnetofliud energy distribution, flow control for the large-scale inlet, flow control near the wall,as well as flow control on the leading edge. The numerical research on magnetofliud flow control has been done in two dimensions, while the job about magnetofliud generator and magnetofliud accelarater has been performed in three dimensions. However, they could not reflect the medium complicated constitutive relation and electromagnetic effect caused by electrons and ions. This program consists of the following subitems: confirming the key mechanism and parameters in aeroheating control of hypersonic aircraft by analysing the basic characteristics of aeroheating dynamics and heating electromagnetic effect of high temperature and hypersonic compressible magnetofliud; grasping the operating principles of magnetofliud producer and magnetofliud accelarater; analyzing and studying the physical machanism of the major magenetofliud shock wave control technology and the magnetofliud control technology of the boundary layer separation in three dimensions. This program is the fundamental research of magnetofliud flow control technology, which might be a perfect technical reserve for how magnetofliud flow control technology and magnetofliud energy-bypass technology is applied to hypersonic aircrafts.

近年来，磁流体动力学在高超声速飞行器上的应用已成为世界各航空航天大国研究的热点问题。目前磁流体技术研究主要集中在以下四个方面：基于磁流体的能量分配发动机技术，大尺度进气道流动控制技术，近壁面流动控制技术，前缘流动控制技术。现有文献对磁流体流动控制采用二维计算，虽然对磁流体发生器和磁流体加速器进行了三维数值模拟研究，但并不能很好地反映磁流体部件内部复杂的介质本构关系和特有的由电子和离子引起的电磁效应。本项目将分析高温、高速可压缩磁流体的气体热动力学及热电磁效应的基本特性，以及确定其对高超声速飞行器热气动控制的关键机制与参数；掌握磁流体发生器、磁流体加速器等关键分系统的工作原理；分析研究三维情况下大尺度磁流体激波控制和边界层流动分离磁流体控制技术的物理机理。本项研究为磁流体流动控制相关技术的基础性研究，将为磁流体流动控制技术和磁流体能量旁路技术在高超声速飞行器上的应用提供良好的技术储备。

近年来，磁流体动力学在高超声速飞行器上的应用已成为世界各航空航天大国研究的热点问题。基于磁流体能量分配的动力系统技术和多尺度磁流体流动控制技术的磁流体旁路冲压发动机推进系统，在一定程度上可以提高超燃冲压发动机的燃烧效率和推力特性，为提高高超声速飞行器的飞行性能提供了可行方案。前缘磁流体流动控制技术，可以改变近壁面流动的物理量梯度，从而降低当地的壁面热流密度，为高超声速飞行器前缘的热防护难题提供了新思路。基于此，本项目分析了高温、高速可压缩磁流体的气体热动力学及热电磁效应的基本特性，建立了可用于高超声速磁流体动力学的基本模型，推导并给出了一个适于任意磁场布置形式的低磁雷诺数近似下磁流体湍流的非线性涡粘性k-ω模型，并对高超声速热化学非平衡流动振动-离解耦合效应开展了机理研究，建立了振动-离解耦合效应的约化模型。对多种形式的磁流体发生器进行了数值模拟研究，掌握其工作原理，分析并总结了磁流体发生器的热电磁流动特性和发电性能；对多种外形结构开展磁流体激波控制技术研究，分析并总结了磁流体控制技术的物理机理和规律。本项研究为磁流体流动控制相关技术的基础性研究，将为磁流体流动控制技术和磁流体能量旁路技术在高超声速飞行器上的应用提供良好的技术储备。