Research On The Matching Of Vane Diffuser With Impeller And Volute In Nuclear Main Pump

At present,facing the double pressure of energy crisis and environmental problems,the development of clean,economic and sustainable energy has become the general trend.As a clean energy,nuclear power can not only reduce the consumption of non-renewable energy such as coal,but also reduce the emission of air pollutants.It is therefore an inevitable choice for the healthy and sustainable development of China's economy and society.The nuclear main pump,also known as the nuclear reactor coolant circulation pump,is the key equipment in the nuclear island.It is the only high-speed rotating equipment of the nuclear steam supply system in the nuclear power plant,playing a vital role in the safe and efficient operation of the reactor.Currently,with the support of the National Key Basic Research and Development Plan(973 Program)for 10 years,and through the joint efforts of many researchers in several universities and related companies in China,we have achieved many Proud achievements,but there are still deficiencies in key design and manufacturing technologies,coupled with foreign technology monopolies,there is still a long way to go to achieve the localized R & D and manufacturing of nuclear main pumps.First,based on the full-scale model pump of the AP1000 nuclear main pump designed independently by the research group,the three-dimensional turbulent flow in the pump was calculated by numerical simulation.The results show that there are unreasonable matching between the guide vanes and the impeller,the guide vanes and the volute.Focusing on the two factors of the radial length of the guide vanes of the model pump and the area ratio of the outlet of the impeller to the inlet of the guide vanes,further in-depth research was conducted.Afterwards,the effect of the radial length of the guide vanes of the model pump on its hydraulic performance was analyzed using numerical experiments.Through the calculation of the flow in the model pump with different length guide vanes,it is found that the model pump with 90% radial vane length has relatively best hydraulic performance.Finally,on the basis of the optimal radial length of the guide vane,an orthogonal experiment was designed based on the parameters determined by the area ratio principle to analyze the effect of the area ratio of the guide vane inlet to the impeller outlet on the internal flow and external characteristics of the pump.Studies have shown that when the area ratio is 0.6314,the matching of the guide vanes of the model pump with the impeller and the volute is the best,the overall performance of the nuclear main pump is relatively optimal.