摘要
为实现迅速抽真空,提出负压储备舱技术。结合流导方程和气体热力学理论,推导出舱体间气流平衡的数学方程式,揭示了气流平衡过程中,舱体间瞬时压差与起始状态压差、舱体容积成正比,与持续时间存在指数关系,与连接管路流导存有反比关系。基于流体微分方程和湍流模型建立非定常流场模型,对压力平衡过程进行动态仿真,从流场角度揭示了瞬时压力与时间的关系。为使负压储备舱实现技术要求,从气压和时间角度进行影响因素分析,研究表明,负压储备舱容积至少为70倍试验舱容积,且连通口面积须有可调性。通过模型结果与试验结果对比,验证了所建两种模型的正确性,也验证了试验装置的可行性。
A novel technique was developed to rapidly pump a apace-craft cabin with a negatively pressured cabin. The equation, describing airflow balance between two cabins, was deduced, based on fluid conductance equations and gas thermodynamics. The equation reveals that in balancing of air flow, the instantaneous pressure-difference between two cabins is directly proportional to the initial pressure-difference and cabin volume, but inversely proportional to the fluid conductance of interconnected pipeline,and evolves exponentially with time, In addition, the dynamical process to reach pressure equilibrium was modeled with unsteady flow field based on fluid differential equations and turbulence model, and simulated. The simulated results show the time dependence of instantaneous pressure from flow field perspective. The im- pacts of the pumping conditions were evaluated for cabin design optimization. The results show that the volume of nega- tively pressured cabin should be at least 70 times bigger than the one to be pumped , and the interconnector should have and adjustable cross-sectional area. The experimental results strongly support the novel technique and its engineering fea- sibility.
出处
《真空科学与技术学报》
EI
CAS
CSCD
北大核心
2013年第12期1191-1198,共8页
Chinese Journal of Vacuum Science and Technology
关键词
真空技术
负压储备
压力平衡
数学表达式
有限元模型
Vacuum technique, Negative pressure reserve, Pressure balance, Mathematical expression
finite elementmodel
