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磁流体发电是解决以冲压发动机为动力的飞行器机载供电问题的有效途径。为了探究磁流体发电通道的内部流动情况和能量转化机理,针对分段法拉第型发电通道,结合实验设备设计参数,构建了低磁雷诺数条件下的磁流体五波模型,并运用二阶熵格式对其求解。通过分析四种不同情况,研究了分段法拉第型磁流体发电通道在不同实验条件下的流动特性。计算结果表明:磁作用数由0变为0.1时,通道出口处温度升高10.4%,出口速度降低27.7%,马赫数降低25%,磁作用数升高至1时,出口速度将降至临界声速,马赫数降为1,出口温度较基准态升高20.8%;通道能量转化率越高,通道内壁逆压梯度越大,流动在内壁上容易发生分离;负载系数为0.5时,通道出口速度相较于负载系数为0.8的情况,气流速度下降约11.7%,马赫数下降8%,通道将产生更多的焦耳热,能量转化率较高,但是电效率较低。通道在进行发电实验时,增大电磁作用强度,同时选择合适的外部负载,可以提高通道发电性能。
Magneto-fluid power generation is an effective way to solve the problem of on-board power supply of ramjet-powered aircraft. In order to explore the internal flow and energy conversion mechanism of the magnetoelectric power generation channel, a five-wave model of the magnetic fluid under low magnetic Reynolds number was constructed for the sectional Faraday-type power generation channel with the design parameters of the experimental equipment. The second-order entropy format Solve it. By analyzing four different conditions, the flow characteristics of the Faraday-type magnetoelectric power generation channels under different experimental conditions were studied. The calculation results show that when the magnetic effect number changes from 0 to 0.1, the outlet temperature increases by 10.4%, the outlet velocity decreases by 27.7% and the Mach number decreases by 25%. When the magnetic effect number increases to 1, the outlet velocity will drop to the critical value The speed of sound and the Mach number decrease to 1, the outlet temperature increases by 20.8% compared with the reference state; the higher the energy conversion rate of the channel, the greater the pressure gradient on the inner wall of the channel, and the flow easily separates on the inner wall; when the load factor is 0.5, Compared to a load factor of 0.8, the airflow velocity is reduced by about 11.7% and the Mach number is reduced by 8%. The channel will generate more Joule heat with higher energy conversion but lower electrical efficiency. Channel power generation experiments, increasing the intensity of electromagnetic interaction, while selecting the appropriate external load, can improve channel power generation performance.