两相流磁流体发电机的性能研究

The Performance Investigation of Magnetohydrodynamic Generator with Two Phase Flow

通过分析三维磁流体动力学与电磁场方程,对气液两相流磁流体发电机等截面直方通道内的流体流动现象进行数值模拟,分别研究了通道截面尺寸、空泡率、磁场强度、入口速度、负载系数、工质对对磁流体发电机的性能影响。数值模拟结果表明,当负载系数为0.5时输出功率达到最大,输出功率与磁场强度、流动速度和工质对中混合导电率成正比关系,同时输出功率与空泡率成反比关系。磁流体发电通道尺寸越大输出功率越大,但输出效率与发电通道尺寸形状密切相关,笔者研究的两个尺寸模型,较小模型由于边界层射流增强及电流聚集的存在使其效率较高。

The effect of different parameters on magnetohydrodynamic(MHD) generator with two phase flow is investigated by three-dimensional numerical simulation and theoretical analysis. The basic parameters contain the dimension of generator, void fraction, magnetic field intensity, inlet velocity, load factor and mixture of fluid. The results show when the load factor is 0.5, the electric power output becomes largest. The power output increases with the increasing of magnetic field intensity, inlet velocity and the electrical conductivity of mixture fluid, and it decreases while the void fraction increasing. Moreover, the results show also that the larger the size of the MHD generation channel, the greater the output power is, but the generator efficiency for a smaller channel is greater than that of larger channel because of velocity in the sidewall boundary layer developed rapidly and electric current gathered.