Study On Surface Texture Of Bearing Of High Temperature Molten Salt Pump In Molten Salt Reactor

In a sense,the transformation of energy structure is a process of transition from traditional fossil energy to new energy.It is not only to solve the self-sustainability of energy supply,but also to solve the environmental problems arising from the use of energy.Nuclear energy is a good substitute for fossil energy,and it also has the characteristics of low carbon and environmental protection,which perfectly corresponds to the problems encountered in the current energy use in China.Thorium-based Molten Salt Reactor(TMSR)has being developed in Shanghai Institute of Applied Physics,Chinese Academy of Sciences.The molten salt reactor has the advantages of unique economic and inherent safety.In this advanced reactor,FLiBe is used as coolant,the heat energy is utilized by the Braytom Cycle,therefore it has good application foreground.China is a depleted uranium country,but the reserves of thorium resources are very rich,ranking in the forefront of the world.Using thorium as fuel is a good technical solution to China's long-term energy supply.The high-temperature molten salt pump is the heart to circulate the coolant in a molten salt circuit.The present molten salt pump equipped to molten salt reactor is a centrifugal sump-type pump with a long shaft which is supported by a bearing in molten salt.Sliding bearings play a key role in the long-term reliable operation of the pump,directly affecting the service life of the pump.The main research content of this subject is to use FLUENT software to study the surface texture of the bearing under the high temperature molten salt pump,analyze the shape of the texture and the influence of various shape parameters on the bearing capacity of the bearing.Through the calculation and design,the surface texture suitable for high-temperature molten salt pump is screened,and the technical reserve for the development of the molten salt pump bearing is made.By studying the relationship between eccentricity and bearing capacity,the following conclusions are obtained: as the eccentricity increases,the bearing capacity of the bearing increases.When the eccentricity is less than 0.7,the bearing capacity changes less with the increase of the eccentricity.When the eccentricity is greater than 0.7,the bearing capacity increases rapidly as the eccentricity increases.In practical applications,the influence of eccentricity should be fully considered.In practical application,the influence of eccentricity should be fully considered.When the eccentricity is large,the bearing has better load capacity,but too large eccentricity can easily cause bearing burnt and journal sticking.Attention should be paid to avoiding such accidents.Circular texture,square texture,long strip texture,and cross-shaped texture can improve the bearing capacity of the bearing in varying degrees.The circular texture bearing capacity increased by 7.7%,the square texture increased by 10.6%,the long strip texture increased by 13.6%,and the cross-shaped texture increased by 21.3%.After comparing the geometric parameters of circular texture,square texture and long strip texture,it is found that the best depth of the four textures is around 20?m.