液氦铁路槽车储槽热响应数值研究

Numerical Study on Thermal Response of Liquid Helium Railway Tank

以某85m^3液氦铁路槽车储槽为研究对象,考虑液氦及氦气物性的变化,采用有限体积法进行了非稳态热响应数值研究,得到了不同时刻的储槽压力、温度及流速分布,分析了蒸发率和充装率对储槽压升、温升规律的影响。研究表明:随着模拟时间的增加,液氦出现了热分层,压力呈上部小、下部大的阶梯式分布,而气相空间压力分布较为均匀;近壁区液氦受热后,在浮升力作用下沿壁面上升至自由液面后流入液氦主流区;随着蒸发率的增加,储槽气相空间的温升及压升速率增加,而充装率对储槽的温升及压升速率影响较小。

Taking a 85 m^3 liquid helium railway storage tank as the research object,the finite volume method was used to study the non-steady-state thermal response under considering the change of liquid helium and helium properties.Thus the tank pressure,temperature and flow rate distribution at different times were obtained,and the effect of evaporation rate and filling rate on the pressure rise and temperature rise of the storage tank was analyzed.The research showed that with the increase of simulation time,the liquid helium showed thermal stratification.In addition,the pressure was distributed in a stepwise manner which was lower in the upper part,and higher in the lower part,while the pressure distribution in the gas phase space was more uniform;After the liquid helium in the near wall area was heated,it rised along the wall surface to the free liquid surface under buoyancy lift,and then flowed into the main flow area of the liquid helium;As the evaporation rate increased,the temperature rise and pressure rise rate in the gas phase space of the storage tank increased,while the filling rate had less influence on the temperature rise and pressure rise rate.