临界流量计内部流场理论计算研究

摘要

为了获得临界流量计内的流场参数分布情况,按照理想气体一维绝热流动基本关系式建立了临界流量计内部流场的理论计算方法,得到流场参数的计算公式.以公式为基础,分析了流量计输入条件改变引起内部参数变化的规律.计算了某流量计内的流场,得到主要参数沿轴向的分布.找到一种通过公式计算最大允许背压比的方法,能获得正确的计算结果.该流场理论计算研究过程对临界流量计的设计具有一定参考意义.%In order to acquire the parameter distribution of the flow field in critical flow meters,this paper established a the-oretical calculation method of the flow field in critical flow meter based on fundamental relations of one -dimensional ideal gas adi-abatic flow,and developed calculation formulas of flow field parameters in the flow field.Based on the formulas,this paper ana-lyzed the change rule of inner parameters,caused by changing the value of input conditions.The flow field of a flow meter was calculated,and the distribution of the main parameters along the axial direction was gained.A method referring to the calculation of maximum allowable back-pressure ratio was found,being sufficient to gain correct results.The study and calculation process had reference significance to the design of critical flow meter.