The Experts below are selected from a list of 95082 Experts worldwide ranked by ideXlab platform

Roland Schiestel - One of the best experts on this subject based on the ideXlab platform.

  • Partially Integrated Transport modeling method for turbulence simulation with variable filters
    Physics of Fluids, 2013
    Co-Authors: Bruno Chaouat, Roland Schiestel
    Abstract:

    The basis of the partially Integrated Transport modeling method was introduced in papers of Schiestel and Dejoan [“Towards a new partially Integrated Transport model for coarse grid and unsteady turbulent flow simulations,” Theor. Comput. Fluid Dyn. 18, 443 (2005)] and Chaouat and Schiestel [“A new partially Integrated Transport model for subgrid-scale stresses and dissipation rate for turbulent developing flows,” Phys. Fluids 17, 065106 (2005)]. This method provides a continuous approach for hybrid Reynolds averaged Navier-Stokes (RANS)-large eddy simulation (LES) simulations with seamless coupling between RANS and LES regions. The method, like in usual LES techniques, makes use of space filtering in the turbulent field. In the foundation papers cited above and in the main applications considered so far, the filter width has been supposed constant or at least slowly varying. In the present paper, we examine the effect of variable filter width in the model equations and how to account for this effect in p...

  • Partially Integrated Transport modeling method for turbulence simulation with variable filters
    Physics of Fluids, 2013
    Co-Authors: Bruno Chaouat, Roland Schiestel
    Abstract:

    The basis of the partially Integrated Transport modeling method was introduced in papers of Schiestel and Dejoan [''Towards a new partially Integrated Transport model for coarse grid and unsteady turbulent flow simulations,'' Theor. Comput. Fluid Dyn. 18, 443 (2005)] and Chaouat and Schiestel [''A new partially Integrated Transport model for subgrid-scale stresses and dissipation rate for turbulent developing flows,'' Phys. Fluids 17, 065106 (2005)]. This method provides a continuous approach for hybrid Reynolds averaged Navier-Stokes (RANS)-large eddy simulation (LES) simulations with seamless coupling between RANS and LES regions. The method, like in usual LES techniques, makes use of space filtering in the turbulent field. In the foundation papers cited above and in the main applications considered so far, the filter width has been supposed constant or at least slowly varying. In the present paper, we examine the effect of variable filter width in the model equations and how to account for this effect in practical numerical simulations. With the aim to illustrate the theoretical development of the effect of varying filter width in time and space on the governing equations of mass, momentum, and turbulence model, and to show the usefulness of the proposed approach, we perform then numerical simulations of isotropic decaying turbulence. (C) 2013 AIP Publishing LLC.

Bruno Chaouat - One of the best experts on this subject based on the ideXlab platform.

  • Partially Integrated Transport modeling method for turbulence simulation with variable filters
    Physics of Fluids, 2013
    Co-Authors: Bruno Chaouat, Roland Schiestel
    Abstract:

    The basis of the partially Integrated Transport modeling method was introduced in papers of Schiestel and Dejoan [“Towards a new partially Integrated Transport model for coarse grid and unsteady turbulent flow simulations,” Theor. Comput. Fluid Dyn. 18, 443 (2005)] and Chaouat and Schiestel [“A new partially Integrated Transport model for subgrid-scale stresses and dissipation rate for turbulent developing flows,” Phys. Fluids 17, 065106 (2005)]. This method provides a continuous approach for hybrid Reynolds averaged Navier-Stokes (RANS)-large eddy simulation (LES) simulations with seamless coupling between RANS and LES regions. The method, like in usual LES techniques, makes use of space filtering in the turbulent field. In the foundation papers cited above and in the main applications considered so far, the filter width has been supposed constant or at least slowly varying. In the present paper, we examine the effect of variable filter width in the model equations and how to account for this effect in p...

  • Partially Integrated Transport modeling method for turbulence simulation with variable filters
    Physics of Fluids, 2013
    Co-Authors: Bruno Chaouat, Roland Schiestel
    Abstract:

    The basis of the partially Integrated Transport modeling method was introduced in papers of Schiestel and Dejoan [''Towards a new partially Integrated Transport model for coarse grid and unsteady turbulent flow simulations,'' Theor. Comput. Fluid Dyn. 18, 443 (2005)] and Chaouat and Schiestel [''A new partially Integrated Transport model for subgrid-scale stresses and dissipation rate for turbulent developing flows,'' Phys. Fluids 17, 065106 (2005)]. This method provides a continuous approach for hybrid Reynolds averaged Navier-Stokes (RANS)-large eddy simulation (LES) simulations with seamless coupling between RANS and LES regions. The method, like in usual LES techniques, makes use of space filtering in the turbulent field. In the foundation papers cited above and in the main applications considered so far, the filter width has been supposed constant or at least slowly varying. In the present paper, we examine the effect of variable filter width in the model equations and how to account for this effect in practical numerical simulations. With the aim to illustrate the theoretical development of the effect of varying filter width in time and space on the governing equations of mass, momentum, and turbulence model, and to show the usefulness of the proposed approach, we perform then numerical simulations of isotropic decaying turbulence. (C) 2013 AIP Publishing LLC.

Liang Shuangbo - One of the best experts on this subject based on the ideXlab platform.

  • Temporal and Spatial Evolution of Integrated Transport Accessibility in the Yangtze River Delta:1986-2005
    Progress in geography, 2010
    Co-Authors: Liang Shuangbo
    Abstract:

    Based on the Integrated Transport network in 1986,1994 and 2005,choosing weighted mean travel time as the indicator,the temporal and spatial evolution of Integrated Transport network and its accessibility are elaborated,and some conclusions are drawn as follows.(1) The speedy development of Integrated Transport net-work results in the continual improvement of accessibility,which is faster in the second period(1994-2005) than that in the first period(1986-1994).The optimal region of Integrated accessibility is Shanghai and the zone along the Taihu Lake in three time section.The sub-optimal region of Integrated accessibility was "-shaped" that consisted of the zone along the Shanghai-Nanjing route and the Shanghai-Hangzhou route in 1986 and 1994,but it had the "Z-shaped" pattern that consisted of the zone along the Shanghai-Nanjing route,the Yangtze River and the Shanghai-Hangzhou route,and the Hangzhou-Ningbo route.(2) The benefits from the improvement of accessibility are different among the nodes.The changing extent of weighted mean travel time is related to the initial value,and the nodes with high initial value decrease more.The changing rate is higher in the central region than that in the north and south regions.Both the changing extent and the changing rate have different patterns in the different periods.(3) Shanghai has the best in Integrated accessibility,followed by Jiangsu provinces,and Zhejiang province is the worst,but the dominant position of Shanghai is weakening,and the gap between Jiangsu and Zhejiang is narrowing.(4) The standard deviation of Integrated accessibility coeffi-cient decreases in the research period,which shows that the Integrated Transport network in the Yangtze River Delta is improving,but there are different developmental processes among various Transport modes.

Daqing Yun - One of the best experts on this subject based on the ideXlab platform.

Zhang Guo-wu - One of the best experts on this subject based on the ideXlab platform.

  • IOT-Based Intelligent Transportation Systems and the Integrated Transport Information Service
    Journal of Transportation Systems Engineering and Information Technology, 2013
    Co-Authors: Zhang Guo-wu
    Abstract:

    In view of the increasing need of developing urban Transport systems,the 30th conference of "Traffic and Transportation Forum 7+1" addresses the issue of "IOT-Based Intelligent Transportation Systems and the Integrated Transport Information Service".It discusses the definition of the IOT-based intelligent Transportation systems.The practical and new technologies of internet of things(IOT) are introduced into the intelligent Transportation systems(ITS),and the diversified and advanced technologies of intelligent Transportation and artificial intelligent(AI) are also applied in the field of traffic management,information service and vehicle control.The harmony of human,vehicle,road and environment can thus be achieved and urban Integrated Transport system can be formed with high efficiency,punctuality,comfort and low carbon emission.As per the Integrated Transport information service,it is suggested to be with the deep and personalized contents and the user-friendly and intelligent patterns.

  • Integrated Transport and Social-Economic Development: Integrated Transport Outlook in the 12th Five-Years
    Journal of Transportation Systems Engineering and Information Technology, 2012
    Co-Authors: Zhang Guo-wu
    Abstract:

    The growth of Transportation has strong relationship with the social and economic development.The past 11th five-years have witnessed the tremendous changes of every Transport mode.However,the rapid economic growth still cannot completely meet residents' demands in China.The 25th conference of "Traffic and Transportation Forum 7+1" is around the issue of "Integrated Transport and social-economic development".It reviews the achievements in the 11th five-years and prospects the future trend of Transport.The goal and task of the Integrated Transport development in the 12th five-years is outlined,together with the relevant policies and measures in terms of infrastructures,technical installations and Transportation services.The programs are discussed for regional Transport,inter-city Transport,urban Transport,rural Transport and Integrated Transportation hubs,the interaction between social economy and Integrated Transport is analyzed as well.The holding of the conference lays the foundation for the Integrated Transport development in the 12th five-years to some extent.

  • Theoretical System of Integrated Transport Development
    Journal of Transportation Systems Engineering and Information Technology, 2009
    Co-Authors: Zhang Guo-wu
    Abstract:

    The fifteenth conference of "Transport 7+1 Forum" sets its theme as "theoretical system of the Integrated Transport development".The Integrated Transport system,an essential subsystem of the whole national economy system,has its own development rules and generally consists of railway,highway,waterway,air,and pipeline Transport.This conference discusses relevant issues about building theoretical system of the Integrated Transport development.To effectively prompt Integrated Transport development and to train advanced talents for interegrated Transport planning,construction,and management,it analyzes the curriculum design and trainning program for traffic and Transportation education both in demestic and international colleges and universities.It further discusses the probable curriculum design and knowledge framework for the Integrated Transportation education in China.During this conference,the concept of establishing the platform with theoretical research and practical application is put forward,and some suggestions are also proposed for further development.

  • On Integrated Transport Promotion Law of China
    Journal of Transportation Systems Engineering and Information Technology, 2009
    Co-Authors: Zhang Guo-wu
    Abstract:

    The fourteenth conference of "Transport 7+1 Forum" focuses on the Integrated Transport Promotion Law of China.A resource-intensive and environment-friendly Integrated Transport system will be an inevitable choice for China's future Transport development.While,under the market economy condition,it is essential to exert rational constraints and adjustments with laws and regulations to achieve the goal.The conference systematically discusses the Integrated Transport Promotion Law on the legislation necessity,legal hierarchy,relationships with laws related,and its framework.With thorough analysis of China's actual conditions and full integrations of experiences from developed countries and regions,the preliminary draft of the Law is drawn up.Explorations of relevant laws and regulations will strongly promote the development of Integrated Transport system,advance the reform of Transport management system and speed up the legalization process of Transport industry as well.

  • Foundation of Theory and Platform for Integrated Transport
    Journal of Transportation Systems Engineering and Information Technology, 2008
    Co-Authors: Zhang Guo-wu
    Abstract:

    With the establishment of the Integrated Transport Research Center of China,this study,focusing on the foundation of theory and platform for Integrated Transport,explains the synthetically developing trend of the Transport in an incorporate manner.Moreover,the relationship between Transport and other aspects,e.g.,economy,energy sources,environment,and innovation of science and technology,is also discussed.As a result,it is claimed that not only the integration of various Transport techniques but also the Integrated Transport administrative management are both indispensable.Furthermore,the illuminative effects of the system science theories on the intelligent Transport system research are analyzed with the correlative factors in the Integrated Transport system studied.In addition,the application of the comprehensive system theories in the field of Integrated Transport research in the future and the significance of the platform foundation for the Integrated Transport system are respectively explored and demonstrated in consideration of the cooperation of various Transport modes,i.e.,railway,waterage,highway,aviation,and pipeline,the harmonious transfers among different travel modes inside Transport hub,and the operation of diversified urban passenger Transport modes synthetically.