超重力真空海水淡化蒸发室两相流动模拟研究

SIMULATION STUDY ON THE TWO-PHASE FLOW IN THE EVAPORATOR OF THE WIND POWERED SUPER-GRAVITY VACUUM DESALINATION PROCESS

为实现风能对海水淡化单元的直接驱动,从而提高风能利用率,提出了1种新型的风能超重力真空海水淡化技术,并对该技术的关键设备超重力蒸发室内的流体流动和相变行为进行了研究。提出了超重力真空形成理论,据此得出超重力蒸发室主要结构参数的影响规律:增大转速和半径,减小溢流口压力和高度均有助于超重力真空环境的形成。借助CFD软件建立了无相变VOF模型,利用模拟结果优化了超重力蒸发室的结构;建立了有相变空穴模型,模拟结果表明,增设溢流堰的超重力蒸发室旋转时可生成海水常温蒸发所需的真空环境,适合于常温下风力机械能直接驱动,可减少或避免抽真空负荷和能耗。

To power the desalination unit directly by wind turbine, improving the usage rate of the wind energy, a novel wind powered super-gravity vacuum desalination technology was presented in this paper. In addition, the fluid flow behavior and phase change in the key equipment, super-gravity evaporator, were studied. The theory of super-grav!ty vacuum formation was propased, based on which, the effect laws of the structural parameters of super-gravity evaporator were obtained. Increasing the rotating speed and radius, and decreasing the pressure and height ofoverflow port will contribute to the formation of super-gravity vacuum circumstance. In virtue of the CFD software, a VOF model without phase change was proposed, and the simulated results were employed to optimize the structure ofthe super-gravity evaporator; A cavitation model with phase ehange was proposed, andthe results showed that the super-gravity evaporator, by rotating of which the vacuum region necessary for seawater evaporation at room temperature can be obtained, is desirable for the direct usage of the wind mechanic energy.