水嘴内部的湍流数值模拟
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摘要
水嘴内部流动复杂,研究内部湍流对其流动结构优化与湍流模型选择具有重要价值.文章选择k-ε模型、k-ω模型和RSM及它们的修正子模型等8种湍流模型对水嘴内流场进行数值模拟,试验所得出口流量与仿真所得出口流量对比,模拟结果与实验结果一致.对比分析所选区域的压强、湍流耗散率和进出口流量百分比,结果表明,压强会随着流道内部结构的改变而发生明显的变化,湍流耗散率在流体进入阀芯处和流体在阀芯顶部处的变化最为显著.通过对比进出口流量的百分比,在水嘴内部湍流模拟中,k-εstandard、RNG和k-ωstandard湍流模型的精度相较高,而k-ωBSL和SST湍流模型模拟的精度较低.
Due to the complexity of turbulent flow,the turbulence models at the present stage are all modified models. Therefore,different modified models are used to simulate the flow field in different situations,so the simulation accuracy is different. In this paper,we choose the k-ε model,the k-ω model and the ReynoldsStress model(including the modified sub model),altogether eight turbulence models,to simulate the flow field in the faucet. The rationality of the simulation results were proved by the experiment results. According to the simulated results,the pressure of the selected region,the dissipation rate of turbulence and the percentage of import and export flow are compared and analyzed. The results show that the pressure will change obviously with the change of the internal structure of the flow channel,and the dissipation rate of turbulence will be in greatest fluctuation when the fluid enters the spool and the fluid at the top of the spool. Through the analysis and comparison of the percentage of the inlet and outlet flow rate of the faucet,we can see that the accuracy of k-εstandard,RNG turbulence model and k-ωstandard turbulence model is higher than that of other models,while the accuracy of k-k-BSL and SST turbulence model is slightly lower,and the simulated Reynolds stress Omega turbulence model is less accurate than the other models under the faucet condition.
Due to the complexity of turbulent flow,the turbulence models at the present stage are all modified models. Therefore,different modified models are used to simulate the flow field in different situations,so the simulation accuracy is different. In this paper,we choose the k-ε model,the k-ω model and the ReynoldsStress model(including the modified sub model),altogether eight turbulence models,to simulate the flow field in the faucet. The rationality of the simulation results were proved by the experiment results. According to the simulated results,the pressure of the selected region,the dissipation rate of turbulence and the percentage of import and export flow are compared and analyzed. The results show that the pressure will change obviously with the change of the internal structure of the flow channel,and the dissipation rate of turbulence will be in greatest fluctuation when the fluid enters the spool and the fluid at the top of the spool. Through the analysis and comparison of the percentage of the inlet and outlet flow rate of the faucet,we can see that the accuracy of k-εstandard,RNG turbulence model and k-ωstandard turbulence model is higher than that of other models,while the accuracy of k-k-BSL and SST turbulence model is slightly lower,and the simulated Reynolds stress Omega turbulence model is less accurate than the other models under the faucet condition.
引文
[1]邵杰,李晓花,郭振江,等. k-ω湍流模型在流动阻力数值模拟中的应用研究[J].青岛大学学报(工程技术版),2016,31(1):120-124.
[2] TUPOV V B,TARATORIN A A. The choice of turbulence models for steam jets[J]. Procedia Engineering,2017,176:199-206.
[3] GROSS A,FASEL H F. Hybrid turbulence model simulations of hemisphere-cylinder geometry[J]. International Journal of Heat&Fluid Flow,2015,54:28-38.
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[5]陆耀军,周力行,沈熊.不同湍流模型在液—液旋流分离管流场计算中的应用及比较[J].清华大学学报(自然科学版),2001,41(2):105-109.
[6]邱胜,刘小兵,江启峰,等.基于不同湍流模型的混流泵内部流动及性能研究[J].水电能源科学,2017,35(4):169-172.
[7]阮春领,马坤,赖焕新.基于不同湍流模型的离心泵叶轮内部流场分析[J].华东理工大学学报(自然科学版),2014,40(6):798-803.
[8]吕云,谈明高,刘厚林,等.不同湍流模型在斜流泵性能预测中的应用[J].水电能源科学,2017(6):159-162.
[9]王强,侯亚丽,汪建文.不同湍流模型建筑风湍流特征精确性研究[J].工程热物理学报,2017,38(1):108-113.
[10]江帆,黄鹏. Fluent高级应用与实例分析[M]. 2版.北京:清华大学出版社,2018:11-19.
[11]中国国家标准化管理委员会. GB/T 18145-2014,陶瓷片密封水嘴[M].北京:中国标准出版社,2014.
[2] TUPOV V B,TARATORIN A A. The choice of turbulence models for steam jets[J]. Procedia Engineering,2017,176:199-206.
[3] GROSS A,FASEL H F. Hybrid turbulence model simulations of hemisphere-cylinder geometry[J]. International Journal of Heat&Fluid Flow,2015,54:28-38.
[4]王海刚,刘石.不同湍流模型在旋风分离器三维数值模拟中的应用和比较[J].热能动力工程,2003,18(4):337-342.
[5]陆耀军,周力行,沈熊.不同湍流模型在液—液旋流分离管流场计算中的应用及比较[J].清华大学学报(自然科学版),2001,41(2):105-109.
[6]邱胜,刘小兵,江启峰,等.基于不同湍流模型的混流泵内部流动及性能研究[J].水电能源科学,2017,35(4):169-172.
[7]阮春领,马坤,赖焕新.基于不同湍流模型的离心泵叶轮内部流场分析[J].华东理工大学学报(自然科学版),2014,40(6):798-803.
[8]吕云,谈明高,刘厚林,等.不同湍流模型在斜流泵性能预测中的应用[J].水电能源科学,2017(6):159-162.
[9]王强,侯亚丽,汪建文.不同湍流模型建筑风湍流特征精确性研究[J].工程热物理学报,2017,38(1):108-113.
[10]江帆,黄鹏. Fluent高级应用与实例分析[M]. 2版.北京:清华大学出版社,2018:11-19.
[11]中国国家标准化管理委员会. GB/T 18145-2014,陶瓷片密封水嘴[M].北京:中国标准出版社,2014.