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Numerical prediction of inner turbulent flow in conical diffuser by using a new five-point scheme and DLR k-ε turbulence model

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Journal of Central South University 2008年第S1期15卷 181-186页

作者：蒋光彪何永森舒适肖映雄 College of Mathematics and Computational Science Xiangtan University Hunan key Laboratory for Computation and Simulation in Science and Engineering Xiangtan University

The internal turbulent flow in conical diffuser is a very complicated adverse pressure gradient *** k-ε turbulence model was adopted to study *** every terms of the Laplace operator in DLR k-ε turbulence model and pressure Poisson equation were discretized by upwind difference scheme.A new full implicit difference scheme of 5-point was constructed by using finite volume method and finite difference method.A large sparse matrix with five diagonals was formed and was stored by three arrays of one dimension in a compressed *** iterative methods do not work wel1 with large sparse *** algebraic multigrid method(AMG),linear algebraic system of equations was solved and the precision was set at *** computation results were compared with the experimental *** results show that the computation results have a good agreement with the experiment *** precision of computational results and numerical simulation efficiency are greatly improved.

关键词： conical diffuser turbulent flow DLR k-ε turbulence model 5-point scheme algebraic multigrid method(AMG)

A new modified k-ε model accounting for the curvature of the streamline

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Chinese Science Bulletin 1995年第18期40卷 1512-1515页

作者：王少平曾杨兵沈孟育史峰徐忠 Department of Engineering Mechanics Tsinghua University. Beijing 100084 China Department of Power and Mechanics Engineering Xi'an Jiaotong University Xi'an 710049 China

During the past two decades, the k-ε model has played a central role in thecalculation of many of the turbulent flows with scientific and enginneering interest. Howev-er, it appears to be sufficient in predicating the complex turbulent shear layers, such asflowr subjected to curvature and rotations. In the last two decades, a variety of modificationshave been made to the k-ε model to account for many complicating features. In

关键词： k-ε model curvature of the streamline preferential dissipation.

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计算风工程中k-ε模型的边界条件研究

空气动力学学报 2016年第4期34卷 530-535页

作者：郭威张悦福建省交通规划设计院福建福州350004 长安大学公路学院陕西西安710064

从k-ε湍流模型控制方程入手,对两类满足平衡大气边界层理论要求的入口边界条件进行了详细分析,比较了二者的理论差异。然后以我国公路桥梁抗风规范中建议的A类风场为来流条件,定义了相应的k-ε模型常数与壁面条件,使用两类边界条件进... 详细信息

从k-ε湍流模型控制方程入手,对两类满足平衡大气边界层理论要求的入口边界条件进行了详细分析,比较了二者的理论差异。然后以我国公路桥梁抗风规范中建议的A类风场为来流条件,定义了相应的k-ε模型常数与壁面条件,使用两类边界条件进行数值模拟。计算结果表明:两类边界条件结合相应的模型常数与壁面条件,均能在数值模拟中构建基本满足规范要求的平衡大气边界层,但各有其适用范围。在此基础上,对模型常数C1和湍动能耗散率与数值模拟结果之间的关系进行了研究,采用修改模型常数与边界条件的方法,改善了数值模拟结果。

关键词： k-ε 湍流模型平衡大气边界层边界条件

Simulation Analysis of New Energy Vehicle Engine Cooling System Based on k-E Turbulent Flow Mathematical Model

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Energy Engineering 2023年第10期120卷 2325-2342页

作者： Hongyu Mu Yinyan Wang Chuanlei Yang Hong Teng Xingtian Zhao Hongquan Lu Dechun Wang Shiyang Hao Xiaolong Zhang Yan Jin College of Power and Energy Engineering Harbin Engineering UniversityHarbin150001China Extended Range Power System Research Institute Harbin Dongan Auto Engine Co.Ltd.Harbin150000China

New energy vehicles have better clean and environmental protection characteristics than traditional fuel *** new energy engine cooling technology is critical in the design of new energy *** paper used oneand three-way joint simulation methods to simulate the refrigeration system of new energy ***,a k-εturbulent flow model for the cooling pump flow field is established based on the principle of computational fluid ***,the CFD commercial fluid analysis software FLUENT is used to simulate the flow field of the cooling pump under different inlet flow *** paper proposes an optimization scheme for new energy vehicle engines’“boiling”phenomenon under high temperatures and long-time climbing *** simulation results show that changing the radiator’s structure and adjusting the thermostat’s parameters can solve the problem of a“boiling pot.”The optimized new energy vehicle engine can maintain a better operating temperature *** algorithm model can reference each cryogenic system component hardware selection and control strategy in the new energy vehicle’s engine.

关键词： New energy vehicle new energy vehicle engine k-ε turbulent flow mathematical model cooling system PID control

基于Realizable k-ε湍流模型的氨气泄漏数值模拟研究

维普期刊数据库评论

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中国安全生产科学技术 2017年第2期13卷 114-118页

作者：孙恩吉李红果王敏中国安全生产科学研究院北京100012 国家安全生产监督管理总局信息研究院北京100012

针对液氨泄漏事故,为了分析不同泄漏点、不同排风条件下氨气的运移规律,以便合理设置应急处置装备、采取有效措施,基于Realizable k-ε的氨气泄漏有限元数值模拟分析方法,计算了液氨泄漏质量,模拟分析了增加排风口、不同液氨泄漏口及不... 详细信息

针对液氨泄漏事故,为了分析不同泄漏点、不同排风条件下氨气的运移规律,以便合理设置应急处置装备、采取有效措施,基于Realizable k-ε的氨气泄漏有限元数值模拟分析方法,计算了液氨泄漏质量,模拟分析了增加排风口、不同液氨泄漏口及不同液氨泄漏量的氨气扩散规律及浓度变化情况。模拟结果表明:对流排风口位置对于泄漏氨气浓度影响较大,泄漏口位置对泄漏氨气扩散影响不显著;氨气泄漏量的增加使得泄漏口垂直方向氨气浓度显著增加。

关键词： Realizable k-ε 湍流模型氨气泄漏数值模拟

基于Realizable k-ε模型的控制阀流场特性研究

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宁夏大学学报（自然科学版） 2014年第4期35卷 328-331页

作者：李琛马玉山高强任海中国计量学院质量与安全工程学院浙江杭州310018 吴忠仪表有限责任公司宁夏吴忠751100

针对煤化工行业中专用控制阀易于磨损失效的问题,提出一种基于Realizable k-ε的有限元数值模拟分析方法.以不平衡单座式控制阀为研究对象,通过对其内部结构进行简化,得到有限元分析的物理模型,基于Preston磨损经验公式,对控制阀内流场... 详细信息

针对煤化工行业中专用控制阀易于磨损失效的问题,提出一种基于Realizable k-ε的有限元数值模拟分析方法.以不平衡单座式控制阀为研究对象,通过对其内部结构进行简化,得到有限元分析的物理模型,基于Preston磨损经验公式,对控制阀内流场不同初始速度下的压力、体积分数和湍流耗散率的分布特性进行分析.数值模拟结果表明,当初速度小于10m/s时,控制阀表面磨损最小.

关键词： Realizable k-ε 控制阀湍流

MATHEMATICAL　MODELLING　OF　BUBBLE　DRIVENFLOWS　IN　A　NOVEL　ALUMINUM　ELECTROLYSIS　CELL

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中国有色金属学会会刊：英文版 1996年第2期6卷 37-40页

作者： Gao Zhaosheng Li Guoxun Shen Jianyun(Beijing General Research institute for Non-ferrous Metals, Beijing 100088) GEN RES INST NONFERROUS MET BEIJING 100088PEOPLES R CHINA

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关键词： mathematical modelling fluid flow aluminum electrolysis cell k-ε model

Forest Canopy Flow Analysis Using Turbulence Model with Source/Sink Terms

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Journal of Donghua University(English Edition) 2015年第4期32卷 588-593页

作者：杨会付海明 College of Environmental Science and Engineering Donghua University

A computational fluid dynamics( CFD) model was presented to simulate wind flow over a forest canopy for analyzing the wind flow within and above forest canopies. Unlike previous studies on the canopy flow,the effect of canopy contour on the canopy was considered to develop the simulation method into a more general but complex case of wind flow over a forest canopy,using cedrus deodara and cinnamomum camphora. The desire of this work is mainly motivated to provide a rational way for predicting the wind flow within and above vegetation canopies. The model of canopy is not incorporated in the geometrical model,and it uses a porous domain combined with k-ε two-equation turbulence model with source / sink terms. The objectives of this paper are to analyze the contour of pressure and velocity and compare the simulation results with other works and field measurements. Results are encouraging,as the model profiles of mean velocity( u) qualitatively agree well with other works compared with and quantitatively have similar explanations as several authors. In conclusion, it is demonstrated that the adoption turbulence model with source / sink terms for forest canopies is proved to be a physically accurate and numerically robust method. The model and method are recommended for future use in simulating turbulent flows in forest canopies.

关键词： k-ε source / sink terms mean velocity forest canopy

Three-Dimensional Water-Quality Simulation for River Based on VOF Method

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Transactions of Tianjin University 2016年第5期22卷 426-433页

作者： Ao Xuefei Wang Xiaoling Song Mingrui Deng Shaohui Li Songmin State key Laboratory of Hydraulic Engineering Simulation and Safety Tianjin University

In the present study, considering the transport and transformation processes of variables, a threedimensional water quality model for the river system was established, which coupled the volume of fluid(VOF) method with the k-ε turbulence mathematical model. Then, the water hydrodynamic characteristics and transport processes for BOD_5, NH_(3^-)N and TP were analyzed. The results showed that the water surface of convex bank was a little lower than that of concave bank due to the centrifugal force near the bend, and most concentrations were inferior to the type Ⅴ standard indexes of surface water environmental quality. The model validation indicated that the errors between the simulated and monitored values were comparatively small, satisfying the application demands and providing scientific basis and decision support for the restoration and protection of water quality.

关键词： three-dimensional water quality model volume of fluid method k-ε turbulence mathematical model river water quality computational fluid dynamics