CAJ | 학술논문

采用计算流体力学的方法，用k—ε两方程模型封闭N—S方程，对缩径阀门结构进行合理简化，对低浓度煤层气深冷液化装备的管线中，不同变径角度和不同通径缩径阀门的流场、流体流动稳定性及局部阻力系数进行了数值模拟。模拟结果表明：缩径阀门的缩径角度在大于等于50°时，流体脱离边界层现象严重，流体流动出现漩涡，缩径阀门具有较差的过流特性；在相同流动条件下，局部阻力系数随着变径角度的增大而增大。模拟计算结果可为项目建设时管线阀的选型提供参考。
채용계산류체역학적방법，용k—ε량방정모형봉폐N—S방정，대축경벌문결구진행합리간화，대저농도매층기심랭액화장비적관선중，불동변경각도화불동통경축경벌문적류장、류체류동은정성급국부조력계수진행료수치모의。모의결과표명：축경벌문적축경각도재대우등우50°시，류체탈리변계층현상엄중，류체류동출현선와，축경벌문구유교차적과류특성；재상동류동조건하，국부조력계수수착변경각도적증대이증대。모의계산결과가위항목건설시관선벌적선형제공삼고。
In this paper,the method of computational fluid dynamics was adopted,the two-equation model with k-εwas used to close the N-S equation,the structure of the diameter-reduced valve was reasonably simplified,and numerical simulation was made on the flow field,the flow stability of fluid and the local resistance coefficient of the diameter-reduced valves with different taper angle and size which were installed in the pipeline of the cryogenic liquefaction equipment of low-concentration coal-bed methane . The simulated results showed that when the angle of the diameter-reduced valve was equal to or larger than 50 o ,the fluid was seriously divorced from the boundary layer,the fluid flow produced vortex,and the diameter-reduced valve had a poor fluid-passing characteristic;under the same conditions,the local resistance coefficient increased with the increase of the taper angle of the diameter-reduced valve. The simulated results can provide reference for the selection of the valves used in the engineering pipeline.