Strength Analysis And Dimension Design Of Shielded Nuclear Main Pump Flywheel Under Static Working Condition

In pressurized water reactor nuclear power plant,the main equipment of the most critical nuclear primary circuit is the reactor coolant pump(commonly referred to as "nuclear main pump"),at the same time,the nuclear main pump is also the only high-speed rotating equipment,which has also been named as the "heart" of reactor cooling system,and the most important components in nuclear main pump is-the flywheel.Power is directly related to the design of flywheel accidents or other accidents of the reactor under the condition of safety,its function is to return when the power-off accident conditions can guarantee in case of emergency shut down of nuclear primary pump system can still rely on the moment of inertia of the slow speed down,and the heat from the reactor coolant slowly away,and thus,avoid high temperature by the core damage caused by a nuclear,guarantee the safety of nuclear main pump.The research object of this paper is the shielded nuclear main pump multi-layer set heavy metal flywheel.The flywheel is composed of inner hub,heavy metal tungsten alloy and outer retaining ring.The flywheel of this structure was mainly studied by the finite element simulation software ABAQUS.Firstly,the integral stress distribution and contact pressure were calculated by analytical method and finite element method,and the correctness of the model was proved.Secondly,the block tungsten alloy structure was used to obtain the optimal tungsten alloy structure as 12 tungsten alloys.The tungsten alloy layer formed can greatly reduce the high stress area distributed on the retaining ring.Further study the change of the contact pressure between the adjacent tungsten alloy blocks on the contact surfaces of the flywheel,and obtain a suitable gap value of 0.012 m.Finally,the range of interference is calculated.Under the premise of meeting the mechanical strength requirement,because the flywheel is surrounded by the shell and affects the maximum size of the flywheel,in order to make the moment of inertia of the flywheel in a limited space The largest,get the appropriate flywheel size design parameters: the radial dimension of the retaining ring is 0.05 m,the radial dimension of the inner hub is 0.14 m,and the radial dimension of the tungsten alloy layer is 0.1575 m.At the same time,for the sake of safety considerations,Design space for internal hub size design,with an interference of 0.0004 m-0.0008 m.