| With the development of society,nuclear energy is a very important clean energy now.In the production and operation of nuclear power,not only the design safety of the motor itself should be ensured,but also the influence of the connected parts below on the canned motor should be considered.When the coolant of the nuclear main pump passes through the inner channel of the pump and the connecting parts in this paper,it will transfer heat to the canned motor,which will increase the temperature of all parts of the canned motor,causing motor accidents and even leading to partial system failure of the main coolant pump.Therefore,it is very important to explore the temperature field changes of internal components and primary and secondary water of the canned motor,and then to study the temperature field changes of coolant temperature of the lower core main pump and heat shield material and layout for the canned motor to ensure the safe and stable operation of the canned motor.In this paper,based on the computational fluid dynamics(CFD),the finite volume method is used to study the velocity field and temperature field of a canned moto.First of all,Solid Works software is used to build a 3d physical model of the 1/4 computational domain of the whole machine(including solid model of each component of the shielded motor,built-in spiral tube heat exchanger and the model of the underside connecting component).grid Meshing and use Ansys software,and grid independence verification,selects the internal fluid turbulent flow condition(7)SST(8)k-? two equation turbulence model,combining with the actual working condition of boundary conditions are given,the temperature of the motor determines the position under the rated conditions of the liquid field and the pitch distribution characteristics.The temperature distribution of stator windings,stator cores,rotor cores and primary cooling water channels is analyzed in detail.The calculation indicates that the maximum temperature of the armored engine is at the fixed end of the coil.The calculation is compared to theoretical equations to confirm the method and accuracy of the results.Secondly,the influence of coolant temperature in the nuclear main pump on the temperature field of the upper canned motor will cause lubrication failure of the internal guide bearing.Therefore,the influence of coolant temperature in the nuclear main pump on the primary cooling water,the lower guide bearing,the heat shield and the stud temperature field of the motor are analyzed.It was found that the coolant temperature of the nuclear main pump had little influence on the upper temperature of the primary cooling water,but however,the greater impact is the field,the main coolant temperature is lower than the lower and protruding manual bearings,which increased by 3.1 °C and 12 °C respectively.Finally,the insulation effect of the insulation screen is considered.The calculation results show that the heat insulation effect of molybdenum shield is better than that of alloy shield,and two layers of molybdenum shield can achieve the heat insulation effect of four layers of alloy shield.And improved insulation screen material,so that the insulation screen can meet the requirements of insulation,but also reduce the cost of manufacturing.The search methods and the result of this article can be numerical simulations of the temperature field of the undefined control system. |
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