摘要
在斯特林制冷机中一般采用间隙密封代替接触密封。间隙密封具有无磨损、不产生污染物、密封性能稳定的特点,但是由于有间隙存在,当间隙两端的压力不相等时就会造成间隙内气体的泄漏,导致制冷机的制冷量减小,影响制冷机的工作寿命和可靠性。利用Materials Explorer软件建立间隙密封的物理模型,通过模拟得到间隙内气体分子和金属原子耦合后运动的状态和过程,进而得到间隙内气体泄漏量与压力以及间隙宽度之间的关系。研究结果表明:从速度矢量上来看,垂直于壁面的原子是不可能泄漏的,只有速度矢量与壁面呈一定夹角的原子才有可能泄漏;随着压力和间隙宽度的增大,泄漏量不断增大。
In a stirling refrigerator,clearance seal was generally used instead of the contact seal with the advantages of no wear,no pollutants,stable sealing performance.However,due to the existence of gap,the unbalanced pressure at both ends of the gap would cause the gas leakage,resulting in the cooling capacity reduction of the refrigerator and affecting its working life and reliability.The physical model of clearance seal was established using Materials Explorer software.The motion state and process of gas molecules and metal atoms in the gap were obtained.And then the relationship between gas leakage and pressure as well as gap width was obtained.The results showed that in terms of velocity vector,the atom leakage wouldn’t occur in the direction normal to the wall.It existed when the velocity vector had an angle to the wall.With the rising of pressure and gap width,the leakage rate increased.
作者
穆德富
祁影霞
孟祥麒
MU Defu;QI Yingxia;MENG Xiangqi(School of Energy and Power Engineering,University of Shanghai for Science and Technology,Shanghai 200093,China)
出处
《能源研究与信息》
2019年第4期205-209,共5页
Energy Research and Information
关键词
斯特林制冷机
间隙密封
泄漏量
分子动力学模拟
stirling refrigerator
clearance seal
leakage
molecular dynamics simulation
