蒸汽排放系统是动力装置的一个重要组成部分,旁路排放箱作为蒸汽排放系统的关键设备,其减压性能主要通过小孔节流来实现,本文针对超临界排放小孔模型开展不同排放参数、不同小孔结构下的节流特性数值模拟研究,建立了小孔超临界压比排放的计算模型,计算结果与理论计算值误差为1.04%,对排放压力5.0 MPa和0.1 MPa两个极端工况进行了模拟,获得了小孔最大马赫数和流量随膨胀比的变化规律及孔径对小孔节流特性的影响,分析了小孔节流减压的作用机理,获得了小孔极限流量值,为旁路排放箱开孔布置提供了设计依据。

The steam discharge system is an important component of the power plant. As a key equipment of the steam discharge system, the bypass discharge box"s pressure reduction performance is mainly achieved through small hole throttling. This article conducts numerical simulation research on the throttling characteristics of the supercritical discharge small hole model under different emission parameters and different small hole structures, and establishes a calculation model for the supercritical pressure ratio discharge of the small hole. The deviation between simulation and theoretical results is 1.04%. Two extreme operating conditions, namely the discharge pressure of 5.0MPa and 0.1MPa, were simulated, and the variation of the maximum Mach number and flow rate of the small hole with the expansion ratio, as well as the influence of the aperture on the small hole throttling characteristics. The mechanism of the small hole throttling pressure reduction was analyzed, and the limit flow value of the small hole was obtained, providing a design basis for the layout of the bypass discharge box opening.

TK221? ???