摘要
为了分析串列式轴流泵的能量特性以及首次级叶轮之间的相互作用及其对能量特性的影响,采用数值计算的方法,对一串列泵内不同流量工况下的内部流场进行计算.湍流模型采用了一种RANS/LES的混合模式的FBM模型,基于试验结果对数值方法进行了验证,结果显示该数值方法能够较为精确地预测轴流泵的能量特性,FBM湍流模型预测结果精度高于标准k-ε模型.串列泵具有和普通轴流泵不同的能量特性:扬程随流量增大单调减小,功率随着流量增大而缓慢增大,说明串列泵具有良好的调节特性;首级叶轮的能量特性随流量变化而改变,具有和普通轴流泵几乎相同的能量特性,次级叶轮的存在明显改善了首级叶轮在小流量工况下的特性;次级叶轮的能量特性和普通轴流泵相比,具有较大差别,这是由于首级叶轮的存在改善了次级叶轮的进口流动,使次级叶轮在较大流量范围内具有恒定的能量特性.
The internal flow in an axial flow tandem pump at various flow rates was computed numeri- cally using CFD code to predict the pump performance of the pump and analyze the interaction between tandem impellers. The FBM turbulence model, in which RANS and LES are blended, was adopted in the computation, and validated against the experimental data, suggesting the model not only is able to predict the performance more precisely but also has a better resolution than the standard k -e turbu- lence model. It was demonstrated that the pump head decreases monotonously but the shaft power rises slightly with increasing flow rate, showing a good regulating characteristic. The front impeller has al- most the same characteristics with conventional axial flow impellers; however, the front impeller per- formance at a low flow rate is clearly improved by the rear impeller. Comparing with conventional axial flow impellers, the rear impeller exhibits a stable head curve over a significantly wide range of flow rate because the flow pattern in its entrance has been improved by the front impeller.
出处
《排灌机械工程学报》
EI
北大核心
2013年第3期210-214,共5页
Journal of Drainage and Irrigation Machinery Engineering
基金
国家自然科学基金资助项目(11172040)
关键词
串列轴流泵
首次级叶轮
FBM湍流模型
能量特性
数值计算
axial flow tandem pump
front and rear irnpellers
FBM turbulence model
energy performances
numerical simulation
