Study On Structural Strength Of High-temperature Hot Water Circulation Pump Applying Thermal-fluid-structure Interaction

High-temperature hot water circulation pump is the key equipment which is widely used for transporting and circulating of hot water in metallurgy,power station,and petrochemical industry.Compared with conventional circulation pump,because of the high temperature and high pressure,the flow passage components of high-temperature hot water circulation pump often appears thermal deformation and stress concentration,which also influences the stability of rotor,and leads to reduce the reliability of pump.This paper is supported by Six Talent Peaks Project in Jiangsu Province(2014-ZBZZ-016)and National Science Foundation of Yangzhou(No.YZ2016116),the purpose is to study the structural strength of pump body and rotor components for high-temperature hot water circulation pump by applying numerical simulation,which is divided into three aspects.Firstly,it is discussed the influences of volute structural parameters on flow field,temperature field,and the structural strength of pump body under high temperature condition.Secondly,it is studied the effects of volute structural parameters on distribution of deformation and equivalent stress for rotor components.Thirdly,it is analyzed the impacts of temperature load or pressure load on pump body structure under different water temperature.The main work is as follows:1.Concluded and sorted out the thermal-fluid-structure interaction,fatigue analysis and modal analysis method.Based on the previous study,the research content has been confirmed,and we concentrate on the structural strength of high-temperature hot water circulation pump with different structure applying thermal-fluid-structure interaction.2.Simulated the fluid domain of pump under three different water temperature.In order to verify the accuracy of numerical simulation method,compared the characteristic curve under ambient temperature with the experiment results.3.Based on the Workbench platform,applied the temperature and pressure load,and defined the boundary conditions for pump body,impeller and pump shaft,then make steady thermal analysis,static analysis and modal analysis.The numerical calculation results of different structural parameters model were compared,which obtained the influence law of cutwater diameter,placed angle of baffle tongue,inlet width and export position of volte on the structural strength pump body and rotor components.Following conclusions had acquired:(1)As for cutwater diameter,the maximum equivalent stress of pump body with the pump body of D3=216mm is smaller,however,the equivalent stress of pump shaft is maximum;placed angle of baffle tongue has a little influence on the flow field,but relatively,the model pump with the different placed angle of baffle tongue has different reliability.(2)With the increase of vortex chamber inlet width,the maximum deformation and maximum equivalent stress of pump body gradually decrease;the equivalent stress of pump shaft and impeller with b3=18mm is smaller;compared with the tangential export,the deformation of pump body with the centre export pump model is relatively larger,as well as the equivalent stress of impeller,pump shaft and shaft head nut;however,for the tangential export of volute,the equivalent stress of pump body is larger.(3)The temperature gradient of fluid near the solid wall gradually increases with the increase of water temperature,which leads to temperature load has an obvious effect on pump body;compared with the effect of pressure load and gravity,the influence of temperature load on the equivalent stress of pump body is gradually enhanced.