摘要
在间隙密封下的高频往复运动活塞组成的热力机械中,活塞平衡位置发生偏移的现象称为活塞偏移现象,这一现象普遍存在。对于线性压缩机和自由活塞斯特林发电机,活塞偏移将导致板簧容易断裂、输出效率下降甚至发生撞缸等严重后果。为研究间隙密封活塞偏移的内部机制以及其影响因素,建立间隙流场的流动泄漏模型,并通过数值模拟验证模型准确性。以百瓦级自由活塞斯特林发电机活塞的密封结构为研究对象,建立热力学和动力学耦合模型,分析间隙和外力对活塞偏移的影响规律。研究表明:一个周期内通过间隙的净泄漏量大于0是导致间隙密封活塞发生偏移的根本原因;在一定条件下,间隙和外力越大,活塞偏移越明显。
It is a common phenomenon that the balance position of the piston is offset in the thermal machinery composed of high-frequency reciprocating piston with clearance seal.For linear compressor and free-piston Stirling generator,the piston offset phenomenon will lead to the fracture of the plate spring,the decrease of output efficiency and the impact between piston and cylinder.In order to study the internal mechanism of the piston offset character under clearance seal and its affecting factors,the flow and leakage model of the clearance was established,and the accuracy of the model was verified through numerical simulation.Based on the sealing structure of the hundred watt free-piston Stirling generator,a thermodynamic and dynamic model was established,and the character of the piston offset caused by the clearance size and the external force was analyzed through the model.The results show that the reason of the piston offset phenomenon is that the net leakage of clearance is greater than zero in one cycle.The piston offset increases with the increase of the clearance size and external force under certain conditions.
作者
杨明卓
焦珂欣
池春云
林明嫱
李瑞杰
牟健
洪国同
YANG Mingzhuo;JIAO Kexin;CHI Chunyun;LIN Mingqiang;LI Ruijie;MOU Jian;HONG Guotong(Key Laboratory of Technology on Space Energy Conversion,Technical Institute of Physics and Chemistry,Chinese Academy of Sciences,Beijing 100190,China;University of Chinese Academy of Sciences,Beijing 100049,China)
出处
《润滑与密封》
CAS
CSCD
北大核心
2024年第4期81-86,共6页
Lubrication Engineering
基金
国家重点研发计划项目(2020YFB1901800)。
关键词
间隙密封
高频往复运动
活塞偏移
线性压缩机
斯特林发电机
clearance seal
high frequency reciprocating
piston offset
linear compressor
stirling generator
