A Study of the Critical Nozzle for Flow Rate Measurement of High-Pressure Hydrogen Gas

作     者：H.D.Kim J.H.Lee K.A.Park T.Setoguchi S.Matsuo 

作者机构：School of Mechanical EngineeringAndong National University388Songchun-dongAndong 760-749Korea Dynamics GroupKorea Research Institute of Standards and SciencePO Box 102YusongTaejon 305-606Korea Department of Mechanical Enginering.Saga University1Honjo—machiSaga-shiSaga 840—8502Japan 

出 版 物：《Journal of Thermal Science》 (热科学学报(英文版))

年 卷 期：2007年第16卷第1期

页      面：28-32页

核心收录：

学科分类：082502[工学-航空宇航推进理论与工程] 08[工学] 0825[工学-航空宇航科学与技术] 

主　　题：critical nozzle compressible flow hydrogen gas ideal gas law real gas effect 

摘      要：The mass flow rate measurement using a critical nozzle shows the validity of the inviscid theory, indicating that the discharge coefficient increases and approaches unity as the Reynolds number increases under the ideal gas law However, when the critical nozzle measures the mass flow rate of a real gas such as hydrogen at a pressure of hundreds bar, the discharge coefficient exceeds unity, and the real gas effects should be taken into account. The present study aims at investigating the flow features of the critical nozzle using high-pressured hydrogen gas. The axisymmetric, compressible Navier-Stokes computation is employed to simulate the critical nozzle flow, and a fully implicit finite volume method is used to discretize the governing equation system. The real gas effects are simulated to consider the intermolecular forces, which account for the possibility of liquefying hydrogen gas. The computational results are compared with past experimental data. It has been found that the coefficient of discharge for real gas can be corrected properly below unity adopting the real gas assumption.