利用AVL F ire软件对SNH4102Z柴油发动机的缸体水套进行了冷却水的流动分布、压力损失及换热性能的CFD分析,然后在原机的基础上进行了优化改进。结果表明:原机缸体水套存在背水侧冷却强度不足、冷却均匀性差的缺点,不能满足缸套冷却要...利用AVL F ire软件对SNH4102Z柴油发动机的缸体水套进行了冷却水的流动分布、压力损失及换热性能的CFD分析,然后在原机的基础上进行了优化改进。结果表明:原机缸体水套存在背水侧冷却强度不足、冷却均匀性差的缺点,不能满足缸套冷却要求。而提出的改进方案明显提高了缸体水套背水侧的冷却强度,改善了缸体冷却的均匀性。展开更多
Conventional model tests and centrifuge tests are frequently used to investigate seepage erosion. However, the centrifugal test method may not be efficient according to the results of hydraulic conductivity tests and ...Conventional model tests and centrifuge tests are frequently used to investigate seepage erosion. However, the centrifugal test method may not be efficient according to the results of hydraulic conductivity tests and piping erosion tests. The reason why seepage deformation in model tests may deviate from similarity was first discussed in this work. Then, the similarity criterion for seepage deformation in porous media was improved based on the extended Darcy-Brinkman-Forchheimer equation. Finally, the coupled particle flow code–computational fluid dynamics(PFC-CFD) model at the mesoscopic level was proposed to verify the derived similarity criterion. The proposed model maximizes its potential to simulate seepage erosion via the discrete element method and satisfy the similarity criterion by adjusting particle size. The numerical simulations achieved identical results with the prototype, thus indicating that the PFC-CFD model that satisfies the improved similarity criterion can accurately reproduce the processes of seepage erosion at the mesoscopic level.展开更多
针对“国家数值风洞”(National Numerical Windtunnel,NNW)工程大型通用“风雷”(Platform for Hybrid engineering simulation of flows,PHengLEI)CFD软件研制的需求,为了提升CFD软件的开发效率,设计与开发了NNW-PHengLEI软件持续集...针对“国家数值风洞”(National Numerical Windtunnel,NNW)工程大型通用“风雷”(Platform for Hybrid engineering simulation of flows,PHengLEI)CFD软件研制的需求,为了提升CFD软件的开发效率,设计与开发了NNW-PHengLEI软件持续集成与测试平台。该平台包含自动化测试、自动化持续集成和代码管理等部分,将现代软件工程中先进的开发模式引入到大型CFD软件开发中来,并结合CFD软件开发的特点,构建了软件开发环境,来促进CFD软件的发展。本文首先介绍了平台的基本框架和总体设计思路,阐述了在PHengLEI软件开发过程中,基于CFD软件开发的特点而设计形成的自动化持续集成方案和更加完善的自动化测试体系,然后给出了自动化测试平台和自动化持续集成在大型CFD软件开发中的应用效果,最后对平台构建的后续工作进行了展望。展开更多
文摘利用AVL F ire软件对SNH4102Z柴油发动机的缸体水套进行了冷却水的流动分布、压力损失及换热性能的CFD分析,然后在原机的基础上进行了优化改进。结果表明:原机缸体水套存在背水侧冷却强度不足、冷却均匀性差的缺点,不能满足缸套冷却要求。而提出的改进方案明显提高了缸体水套背水侧的冷却强度,改善了缸体冷却的均匀性。
基金Project(51309086)supported by the National Natural Science Foundation of ChinaProject(20110094120002)supported by the Ministry Education Foundation of ChinaProjects(2014B04914,2011B07214)supported by the Fundamental Research Funds for the Central Universities,China
文摘Conventional model tests and centrifuge tests are frequently used to investigate seepage erosion. However, the centrifugal test method may not be efficient according to the results of hydraulic conductivity tests and piping erosion tests. The reason why seepage deformation in model tests may deviate from similarity was first discussed in this work. Then, the similarity criterion for seepage deformation in porous media was improved based on the extended Darcy-Brinkman-Forchheimer equation. Finally, the coupled particle flow code–computational fluid dynamics(PFC-CFD) model at the mesoscopic level was proposed to verify the derived similarity criterion. The proposed model maximizes its potential to simulate seepage erosion via the discrete element method and satisfy the similarity criterion by adjusting particle size. The numerical simulations achieved identical results with the prototype, thus indicating that the PFC-CFD model that satisfies the improved similarity criterion can accurately reproduce the processes of seepage erosion at the mesoscopic level.
文摘针对“国家数值风洞”(National Numerical Windtunnel,NNW)工程大型通用“风雷”(Platform for Hybrid engineering simulation of flows,PHengLEI)CFD软件研制的需求,为了提升CFD软件的开发效率,设计与开发了NNW-PHengLEI软件持续集成与测试平台。该平台包含自动化测试、自动化持续集成和代码管理等部分,将现代软件工程中先进的开发模式引入到大型CFD软件开发中来,并结合CFD软件开发的特点,构建了软件开发环境,来促进CFD软件的发展。本文首先介绍了平台的基本框架和总体设计思路,阐述了在PHengLEI软件开发过程中,基于CFD软件开发的特点而设计形成的自动化持续集成方案和更加完善的自动化测试体系,然后给出了自动化测试平台和自动化持续集成在大型CFD软件开发中的应用效果,最后对平台构建的后续工作进行了展望。
