【摘要】 在反渗透海水淡化系统中,旋转式能量回收装置(RERD)由于转子与端盘等部件配合间隙中存在的内部泄漏问题,其能量回收效率这一关键指标受到严重影响.传统的减缓泄漏研究,主要采用穷举性试验,因而工作效率较低且普适性较差.针对这一问题,本文首先通过数值仿真确定了RERD泄漏流体的流动形式,以此为基础定义了各泄漏路径,分别为端面径向泄漏、端面周向泄漏和周面周向泄漏,然后用解析化数学表达式分别表述了这些路径.将解析式所计算的RERD总泄漏量与CFD模拟计算结果相比,两者的相近程度高达94.90%,这意味着解析式能对RERD泄漏流量准确表达.此外,研究证明相同配合间隙下端面径向泄漏路径是装置内部泄漏的主要路径,其泄漏量占装置总泄漏的75.505%,这为解决RERD内部泄漏研究提供了理论依据.更多还原

【Abstract】 In seawater reverse osmosis desalination systems, improving the energy recovery efficiency of rotary energy recovery devices(RERDs), which is a key performance indicator, is limited because of the internal leakage problem caused by the presence of conjugate clearances between the rotor, end covers, and other units. Meanwhile, conventional studies on leakage reduction are not very efficient and cannot be applied in all situations while conducting exhaustive trials. Considering the above, in this study, the flowing forms of RERD leakage are determined through numerical simulation. On this basis, the main leakage routes are defined, including the radial and circumferential forms on the end face and the circumferential form between the annular gaps. Additionally, these respective routes are expressed by analytically derived mathematical formulae. The similarity between the leakage rate predictions from the formulae and from numerical simulations is up to 94.90%, indicating that the formulae can accurately illustrate RERD leakage.Furthermore, under identical conjugate clearances, the radial route was proved to be the dominating route of internal leakage because this route accounts for 75.505% of the total RERD internal leakage; this finding provides a theoretical basis for studies on the internal leakage reduction in RERDs.更多还原