湿蒸气汽轮机叶栅通道内雾滴扩散沉积特性分析

引起湿蒸气汽轮机叶片侵蚀的大水滴是由于雾滴在汽轮机叶片表面上的扩散沉积而产生的．因此，雾滴扩散沉积率的大小对大水滴在湿蒸气中所占的比例及叶片的侵蚀速度有很大的影响．采用边界层内质量传递与动量传递的比拟理论及其半经验关系式，计算并分析了湿蒸气汽轮机叶栅通道内不同尺寸雾滴的扩散沉积特性，以及压力、汽流速度和叶栅节距等参数对扩散沉积率的影响．计算与分析的结果对汽轮机防蚀装置的设计具有一定的参考意义

Analysis of the Diffusive Deposition Characteristics of Fog Droplets on Wet Steam Turbine Blades

Large water droplets which cause erosion of wet steam turbine blades are formed due to the diffusive deposition of fog droplets on blade surface. Therefore, the diffusion deposition rate of fog droplets has great influence on the ratio of large droplets to the moisture in stream and the erosion rate of the blade. The diffusive deposition characteristics of fog droplets with different size were calculated and analyzed by means of applying the mass transfer and momentum transfer analogous theory and semi empirical equations. The effects of working parameters, such as pressure, steam velocity and blade pitch etc., on deposition rate were analyzed. The results are beneficial to the design of anti erotion devices in wet steam turbine.