含沙水流时水轮机工作参数的定义和计算方法

Definition and Computing Method of Operation Parameteres of Hydraulic Turbine Operated in Silt-laden Water Flow

从两相流动观点出发,推导了含沙水流时的伯努利方程式,使其更能真实地反映含沙水流的力学特性;对含沙水流条件下水轮机的工作参数进行了定义,进而推出其具体计算方法。经过与清水条件下的伯努利方程及工作参数进行对比分析,得出了清水与含沙水流能量转换的不同特点。指出了在相同静水头下含沙水流时水轮机的工作水头小于单相液体的工作水头以及水轮机输出功率、效率等参数的变化规律和含沙量的关系。

Proceeding from the viewpoint of two-phase flow,the Bernoulli equation for silt-laden water flow is derived, which reflects real mechanic characteristics of silt-laden water flow. Therefore,the defination and computing method of operating parameteres of hydraulic turbine operated in silt-laden water flow are presented in this paper. On the basis of comparison of the Bernoulli equation and operating parameteres for clean water flow with those for silt-laden water flow,different features of energy transformation in clean water flow and silt-laden water flow are obtained. The operating head of hydraulic turbine operated under the same hydrostatic head is less in the case of silt-laden water flow than in the case of single phase liquid. The varying pattern of the output and the efficiency and their relationship with silt content in the two cases are also pointed out .