Analysis of Cavitation with Rotational Speed and Water Temperature Changes of Centrifugal Pump

Abstract

The focus of interest of this study is to understand the rotational speed and temperature effects on cavitation of centrifugal pump by using computational methods. The Rayleigh-Plesset cavitation model and two-phase homogeneous liquid-vapor method are adapted and performance characteristics are obtained using by the Reynolds averaged Navier-Stokes (RANS) equations with two equation SST turbulence model. The governing equations are discretized by the finite volume method. The head drop curves are obtained for different rotational speeds (3000 rpm, 3200 rpm, 3400 rpm, and 3600 rpm) and the effects on cavitation are described according to different net positive suction head at design flow point (Qd.p.). Also, the development of cavitation performances are described by thermodynamic effects at three different temperatures (15℃, 25℃, and 40℃). At higher temperature (40℃), the cavitation erosion is occurred quickly on the impeller blade than the lower temperature (15℃). Finally, the computed performances are validated with the experimental data and it’s found that both results were a good agreement.