核电汽轮机弯管式汽水分离器的改进结构及其除湿性能

Special Cross-Under Pipe Separators Structure and Moisture Separation Performance of Nuclear Power Steam Turbines

为了提高弯管式汽水分离器的除湿效率,提出了2种汽水分离器改进结构,一种是弯管前加旋流装置的组合分离器,另一种是"Z"字形弯管分离器,同时对改进结构进行了数值研究。结果表明:弯管前加旋流装置的组合分离器中,汽流经过旋流叶栅后流向发生偏转,紊乱的流场持续到第一组导流除湿叶栅进口,汽流经过第二组导流除湿叶栅后流线基本与圆管的轴向一致,汽流经过旋流叶栅和导流除湿叶栅时会产生较大总压损失;"Z"字形弯管分离器管中,汽相流速比较均匀,流线分布良好,总压损失主要发生在导流除湿叶栅中。与弯管式分离器相比,弯管前加旋流装置的组合分离器的除湿效率提高了7.4%,平均总压损失系数增大了28.1%;"Z"字形弯管分离器性能最佳,除湿效率提高了11.3%,平均总压损失系数减小了37.5%。该结果可为研究和开发新型汽水分离器提供理论依据。

To improve the moisture separation efficiency of special cross-under pipe separators（SCRUPS）, two modified separators — combinational separator with a swirl device in front of SCRUPS and “Z” shaped SCRUPS are proposed and numerically investigated. The results show that steam in combinational separator deflects after the swirl blades, and its disordered flow continues to the inlet of the first row of blade cascade and gets homogeneous after the second row. Considerable total pressure loss occurs in swirl blades and blades cascades. Relatively homogeneous steam velocity and fine streamline distribution appear in “Z” shaped separator, and the total pressure loss occurs mainly in blade cascades. Compared with SCRUPS, the combinational separator enhances the moisture separation efficiency by 7.4% and the average total pressure loss coefficient by 28.1% relatively, and the “Z” shaped separator is endowed with the best performance, where the moisture separation efficiency is increased by 11.3%, and the average total pressure loss coefficient is decreased by 37.5%.