核主泵叶轮能量转换与叶片载荷的关联性分析

Analysis of inter relationship of energy conversion in impeller of nuclear main pump to load on blade

为了研究核主泵叶轮能量转换规律与叶片载荷分布规律之间的关联性,基于RNGk-ε湍流模型,对不同流量工况下核主泵模型泵进行全三维定常数值计算.结果表明:从叶片吸力面到压力面,叶片做功能力逐渐增强;为了使叶轮获得较好的水力性能,叶片载荷的变化趋势应保持平缓,且其载荷峰值应在靠近叶轮出口处;根据不同流量工况下的叶轮性能曲线,叶片载荷有最优变化梯度;叶轮叶片中间流线上的动压载荷随着流量的增大逐渐减小,且动压载荷变化幅度较静压载荷更为明显,叶片动压载荷占总载荷的比重越低叶轮效率越高.

In order to investigate inter relationship the energy conversion law of impeller in nuclear main pump and the law load distribution on blade,full three-dimensional steady numerical evaluation is carried out for a modeled nuclear main pump on different working conditions based on RNG k-ε turbulence mode.The result shows that the work done ability of the blade will increase gradually from suction surface to pressure surface of blade,the change trend of blade load has to be gentle to obtain better hydraulic performance of impeller,and the peak point of blade load has to be close at impeller outlet.It is known from the performance curve of the impeller operating under different flow conditions that the blade load will have an optimum variation gradient,the dynamic pressure load along intermediate streamline between two impeller blades will gradually decrease with the increase of the flow rate,the variation amplitude of the dynamic pressure load will be more obvious than that of the static pressure load,and the lower the proportion of dynamic pressure load in total blade load is,the higher the impeller efficiency will be.