关键词: 熔盐泵, 双蜗壳, 变工况, 流场, 径向力

Abstract: With double volute and double discharge pipe,circumferential unevenness of vertically-installed high-temperature molten-salt pump is expected to be relieved.Standard k-ε turbulent model and implicit multi-grid coupling method were used to simulate the whole-passage three-dimensional inner turbulent flow of the pump.Correspondingly,pump performance of single volute and single discharge pipe molten-salt pump was comparatively studied.Comparisons of pressure and velocity distributions,local turbulent kinetic energy distribution,radial forces at impeller and volute were conducted between two different pumps under different flow rate conditions.Energy performance of the single-volute pump was better than that of the double-volute pump.Good adaptability was shown in the flow field of the double-volute pump at large flow rates.For these two different pumps,the radial forces exerted on the impeller and volute were small at the design flow rate.However,this phenomenon varied under off-design conditions.The radial forces on the impeller and volute of the single volute pump increased rapidly,while the double-volute pump showed superiority over the single volute pump in reducing radial forces at the impeller and volute.The flow field in the double-volute pump was not perfectly symmetric,but under large flow rate conditions,the radial forces exerted on the impeller and volute reached minimum values respectively.

Key words: molten-salt pump, double volute, variation of operation condition, flow field, radial forces