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针对表面磁流体(MHD)气动激励对高超声速进气道在非设计状态下激波控制问题,从唯象学的角度出发,基于低磁雷诺数假设,将电磁作用简化为Navier-Stokes方程组中的源项处理,同时考虑到低气压、低磁场环境下电子回旋效应引起的Hall效应,并联立Ohm定律,建立磁流体动力学模型,通过与实验纹影对比验证了模型的合理性,并利用该模型研究了表面MHD加/减速激励作用位置与宽度、磁场强度、电导率和能量转化率等参数对楔面激波的影响规律。结果表明:表面MHD气动激励包括焦耳热与洛伦兹力作用,当放电功率密度为3.8×10~9k W/m~3,磁场强度为0.34T时,MHD加/减速激励分别使激波位置前移6mm与10mm;而磁场强度较低时,由于焦耳热的主导作用,将会出现激波前后压力比增大,激波强度增加等负面效应;根据激励参数的影响规律,激励器电极应靠近尖端布置,增大磁场强度,并改善等离子体源以提高气体电导率,同时适当增大激励区域宽度。
Aiming at the problem of shock control of hypersonic air inlet in non-designed state of aerodynamic excitation of surface MHD, from the perspective of phenomenology, based on the assumption of low magnetic Reynolds number, the electromagnetic effect is reduced to the Navier-Stokes equations And take into account the Hall effect caused by electron gyroscope effect in low pressure and low magnetic field and parallel Ohm’s law to establish the magnetohydrodynamic model and verify the rationality of the model by comparing with the experiment shadow The influence of surface MHD acceleration / deceleration excitation position and width, magnetic field strength, electrical conductivity and energy conversion on the wedge shock wave was studied by using this model. The results show that the surface MHD aerodynamic excitation includes Joule heating and Lorentz force. When the discharge power density is 3.8 × 10 ~ 9k W / m ~ 3 and the magnetic field strength is 0.34T, the MHD acceleration / Forward 6mm and 10mm; and low magnetic field strength, due to the leading role of Joule heat, will appear before and after the shock wave pressure ratio increases, the shock intensity increases and other negative effects; according to the impact of excitation parameters, the actuator electrode should Close to the tip, increasing the magnetic field strength, and improving the plasma source to improve gas conductivity, while appropriately increasing the excitation region width.