【摘要】 为研究多级潜水泵的瞬态运行特性,基于Fluent软件,采用标准k-ε湍流模型,SIMPLEC算法,在滑移网格技术的基础上,对两级模型泵进行三维非定常数值模拟.得到了潜水泵的水力性能并与试验进行对比,计算了不同位置处的压力脉动情况,并对其结果进行了时域和频域分析.结果表明:不同位置点处压力脉动均呈现周期性变化,其周期接近叶轮叶片数,频率接近叶频,而导叶叶片数对压力脉动周期影响较小;叶轮内的脉动频率从叶轮进口到叶轮出口逐渐增加,且在叶轮出口处达到极大值,导叶中则与之相反;压力脉动最剧烈的地方在叶轮出口处,各监测点的主频几乎都为叶频;次级流道叶轮和导叶各监测点压力脉动系数幅值高于首级流道各监测点;次级流道导叶内仍存在2个波峰,压力脉动并未完全消除,两级导叶内监测点主频不同.更多还原

【Abstract】 In order to investigate the transient operation characteristics of multi-stage submersible pumps,three-dimensional,unsteady numerical simulations were conducted by using the standard k- ε turbulence model,SIMPLEC algorithm based on the sliding mesh technique in Fluent. The performance of the pump was obtained and compared with the experimental results. Besides,the pressure pulsations at various monitoring points were acquired; subsequently they were analyzed in time and frequency domains,respectively. It was demonstrated that the pressure fluctuation at all the monitoring points changes periodically with time,its number of periods is identical to the number of blades but less affected by the number of guide vane blades,its frequency is close to the blade passing frequency. The frequency of pressure fluctuation within the impeller increases gradually towards the impeller outlet and approaches the maximum value there,while the variation tendency of the frequency is opposite within the guide vane. The mostly dramatic pressure fluctuation occurs at the impeller outlet,the main frequency at various monitoring points is almost equal to the blade passing frequency. The amplitude of pressure pulsation coefficient at the monitoring points in the second stage impeller is higher than the first stage impeller. There still are two peaks in the pressure pulsation profiles in the second stage guidevane,suggesting pressure pulsation is not eliminated completely there. Additionally,the main frequency of pressure pulsation in the first stage guide vane is different from the second stage guide vane.更多还原