摘要
为研究进气压力对真空发生器性能的影响,利用Fluent软件对真空发生器内部流场进行数值模拟。仿真范围内,通过对真空口处压强、引射效率、气体沿轴线的速度与压强,以及发生器失效的讨论分析,得到如下结论:真空口封闭的瞬态条件下,对真空口处压强而言,进气压力存在临界值与最优值,超过临界值后真空口处压强出现周期性震荡,达到最优值时,能以最优进气压力达到高于该压力所能维持的真空度;基于等压混合假设的稳态条件下,对引射流量、引射效率而言,分别存在相应的进气压力最优值,并于对应最优值时达到最大的引射流量与引射效率。
The flow field in the lab-built device, called vacuum u generatorM and designed by modifying an e-jector,was mathematically modeled and numerically simulated with Fluent software. The influence of the inlet-pressure on the entrainment rate, axial distributions of pressure/velocity, and the lowest pressure obtained was investigated. The simulated results show that the inlet-pressure has a major impact. For example, under the port-closed transient condition , there is a critical inlet-pressure;at the vacuum port, an optimized inlet pressure results in the lowest pressure, whereas an in let-pressure higher than the critical one causes a periodic pressure fluctuation. Moreover, in steady-state isobaric mixing hypothesis, an optimized inlet pressure maximizes the entrainment flow and entrainment rate. We suggest that the simulated results be of some technological interest in design and application of the vacuum “generator.”
作者
刘宝
韩威震
张业明
张柯
Liu Bao;Han Weizhen;Zhang Yeming;Zhang Ke(School of mechanical and power engineering, Henan polytechnic university, Jiaozuo 454000, China)
出处
《真空科学与技术学报》
EI
CAS
CSCD
北大核心
2019年第4期304-309,共6页
Chinese Journal of Vacuum Science and Technology
关键词
真空
数值仿真
进气压力
震荡
真空度
Vacuum
Numerical simulation
Inlet pressure
Shock
Vacuum degree
