Analysis and numeric simulation of off-design flow field in centrifugal pump

By adopting time averaged N-S equations and RNG k-e mode,the impeller-volute coupling characteristics were simulated with SIMPLEC algorithm.Based on the analysis of off-design flow field,the radial force calculation model was established,and the radial forces were respectively calculated for different flow rate conditions,also.The results revealed that the maximal radial force occurred in the condition of low flow rate,and the minimal radial force occurred in the condition of large flow rate.In the former case,the vector direction of radial force took place in the range from section Ⅲ to section Ⅴ.In the latter case,the same in the range from section Ⅶ to the tongue.It was found by comparing numerical prediction with "Stepanoff" results that the error was within 2% under design condition and 5% under off-design conditions.