大管径八流道直流喷嘴涡流管流动与传热数值模拟

Numerical Simulation of Flow and Heat Transfer in A Large-diameter Eight-Flow DC Nozzle Vortex Tube

为了充分掌握大管径涡流管内流场分布规律和能量分离原理,将涡流管更好地应用于气田现场,本文构建了大管径八流道直流喷嘴涡流管三维计算模型,以甲烷作为工质气体进行数值模拟研究,并对相关特征物理量进行了研究分析。研究结果显示当工质气体入口总压为0.5 MPa、入口总温为290 K时,改变热端出口背压,随冷流率变化,涡流管最大制冷、制热温差分别达到29 K和18 K,最大单位制冷、制热量达到17.25 kJ和15.43 kJ,并且同一冷流率下,工质气体的单位制冷量要高于单位制热量;涡流管内部内外旋流气体之间的相互作用是能量相互传递、总温产生分离的基础。以上成果认识,对进一步将涡流管技术应用于天然气工业现场,解决气田现场存在的工程技术难题具有指导和借鉴价值。

In order to fully grasp the flow field distribution law and energy separation principle in large diameter vortex tube,the vortex tube is better applied to the gas field,this paper constructed a three-dimensional calculation model of large diameter eight-channel DC nozzle vortex tube,with methane as working fluid.The gas was numerically simulated and the physical quantities of related features were studied and analyzed.The results show that when the total inlet pressure of the working gas is 0.5 MPa and the total inlet temperature is 290 K,the back pressure of the hot end is changed,and the maximum cooling and heating temperature of the vortex tube are 29 K and 18 K respectively.The heating capacity reaches 17.25 kJ and 15.43 kJ and the unit cooling capacity of the working gas is higher than the unit heating capacity under the same cold flow rate.The interaction between the internal and external swirling gas inside the vortex tube is the mutual energy transfer.The temperature produces the basis of separation.The above achievements have a guiding and reference value for further application of vortex tube technology to the natural gas industry site to solve the engineering and technical problems existing in the gas field.