Experimental Study And Loss Prediction Of High Pressure Stage Blades Of Nuclear Power Turbine Unit

High efficiency steam turbine is very important to improve the efficiency of nuclear power plant.At the same time,improving the aerodynamic performance of blades and reducing the loss of blade shape are of great value in engineering application.In this paper,the high-pressure 7th stage blade of the nuclear power plant steam turbine unit in Harbin steam turbine works is studied,including the dynamic and static blade plane cascade blowing test and static blade annular cascade blowing test.The test results are analyzed and compared,and the aerodynamic characteristics and loss mechanism of this stage blade are obtained,and the test results are analyzed with the aid of numerical simulation.In this paper,the loss prediction models proposed by scholars at home and abroad are also summarized,and the corresponding loss calculation program is developed to predict the loss of the 7th stage stationary blade of high pressure,and the loss model suitable for this set of blade profile is given,which provides technical support for the subsequent modification design of this blade profile.First of all,the aerodynamic performance of the three cross-section airfoils with variable angle of incidence(-20,-10 °,0 °,10 °,20 °)at the three blade heights(10%,50%,90%)of the moving and stationary blades was studied on the plane cascade testbed.The static pressure coefficient distribution,outlet air flow angle distribution and total pressure coefficient distribution curves of each section airfoil at different operating points were obtained.According to the analysis of the test results,the following conclusions are drawn: both the moving and stationary blades are of post loading type,which have good adaptability to negative attack angle;compared with the moving blade type,the static blade type has stronger adaptability to attack angle,better loss control ability,and all the blades are suitable for small negative attack angle inflow,etc.Secondly,the annular cascade test is carried out on the stator,and the variable angle performance of the stator is simulated by the numerical simulation software.The aerodynamic characteristics and loss control of the stator are compared and verified by the test results and simulation results.The analysis results show that the design of positive bending is adopted in the stator,and the loss control at the upper and lower wall is better;the maximum loss occurs at the blade root;the stator is more sensitive to the flow from the positive angle of attack,when the positive angle changes,the loss area expands,the loss peak increases,and the loss at the blade root is more obvious than that at the blade top.Finally,in order to further discuss the loss mechanism and loss control of the stator blade,a variety of loss prediction models proposed by scholars at home and abroad in recent years are reviewed and summarized.A set of calculation program is developed to predict the loss of the stator blade,and the results are compared with the test results.The results show that: for the seventh stage of high-pressure stator blade,no matter the total loss at the design point The Moustapha model can predict the loss accurately,which provides a good technical reference for the engineering modification and practical application of this stage of blades.