跳至主要内容

Modelling Turbulent Heat Transfer in a Natural Convection Flow

Read full paper at:
http://www.scirp.org/journal/PaperInformation.aspx?PaperID=47028#.VGLy92fHRK0

In this paper a numerical study of a turbulent, natural convection problem is performed with a compressible Large-Eddy simulation. In a natural convection the fluid is accelerated by local density differences and a resulting pressure gradient. Directly at the heated walls the temperature distribution is determinate by increasing temperature gradients. In the centre region convective mass exchange is dominant. Density changes due to temperature differences are considered in the numerical model by a compressible coupled model. The obtained numerical results of this study are compared to an analogue experimental setup. The fluid properties profiles, e.g. temperature and velocity, show an asymmetry which is caused by the non-Boussinesq effects of the fluid. The investigated Rayleigh number of this study lies at Ra = 1.58 × 109.
 
Cite this paper
Zimmermann, C. and Groll, R. (2014) Modelling Turbulent Heat Transfer in a Natural Convection Flow. Journal of Applied Mathematics and Physics, 2, 662-670. doi: 10.4236/jamp.2014.27073
 

[1] Tian, Y.S. and Karayiannis, T.G. (2000) Low Turbulence Natural Convection in an Air Filled Square Cavity, Part I: The Thermal and Fluid Flow Fields. International Journal of Heat and Mass Transfer, 43, 849-866.
http://dx.doi.org/10.1016/S0017-9310(99)00199-4
[2] Sutherland, W. (1893) The Viscosity of Gases and Molecular Force. Philosophical Magazine, Series 5, 36, 507-531.
http://dx.doi.org/10.1080/14786449308620508
[3] Fureby, C. (1996) On Subgrid Scale Modeling in Large Eddy Simulations of Compressible Fluid Flow. Physics of Fluids, 8, 1301-1311. http://dx.doi.org/10.1063/1.868900
[4] Vreman, B. (1995) Direct and Large-Eddy Simulation of the Compressible Turbulent Mixing Layer. Ph.D. Thesis, University of Twente, Enschede.
[5] Kenjeres, S. and Hanjalic, K. (1999) Transient Analysis of Rayleigh-Bénard Convection with a RANS Model, International Journal of Heat and Fluid Flow, 20, 329-340.
http://dx.doi.org/10.1016/S0142-727X(99)00007-7
[6] Sergent, A., Joubert, P. and Quéré, P. Le (2003) Development of a Local Subgrid Diffusivity Model for Large-Eddy Simulation of Buoyancy Driven Flows: Application to a Square Differentially Heated Cavity. Numerical Heat Transfer, Part A: Applications, 44, 789-810.
[7] Shishkina, O. and Wagner, C. (2008) Analysis of Sheet-Like Thermal Plumes in Turbulent Rayleigh-Bénard Convection. Journal of Fluid Mechanics, 599, 383-404. http://dx.doi.org/10.1017/S002211200800013X
[8] Shishkina, O. and Thess, A. (2009) Mean Temperature Profiles in Turbulent Rayleigh-Bénard Convection of Water. Journal of Fluid Mechanics, 633, 449-460. http://dx.doi.org/10.1017/S0022112009990528
[9] Kosovic, B., Pullin, D.I. and Samtaney, R. (2002) Subgrid-Scale Modeling for Large-Eddy Simulations of Compressible Turbulence, Physics of Fluids, 14, 1511-1522. http://dx.doi.org/10.1063/1.1458006
[10] Erlebacher, G., Hussaini, M.Y., Speziale, C.G. and Zang, T.A. (1992) Toward the Large-Eddy Simulation of Compressible Turbulent Flows. Journal of Fluid Mechanics, 238, 155-185.
http://dx.doi.org/10.1017/S0022112092001678
[11] Gifford, W.A. (1991) Natural Convection in a Square Cavity without the Boussinesq-Approximation. 49th Annual Technical Conference-ANTEC’91, Montreal, 5-9 May 1991, 2448-2454.
[12] Mergui, S., Penot, F. and Tuhault, J.H. (1993) Experimental Natural Convection in an Air-Filled Square Cavity at . In: Henkes, R.A.W.M. and Hoogendoorn, C.J., Eds., Turbulent Natural Convection in Enclosures—A Computational and Experimental Benchmark Study, Proceedings of the Eurotherm Seminar no 22, Editions Européennes Thermique et Industrie, Paris, 9-108.
[13] King, K.J. (1989) Turbulent Natural Convection in Rectangular Air Cavities. Ph.D. Thesis, Queen Mary and Westfield College, University of London, London, UK.                                             eww141112lx

评论

此博客中的热门博文

Does Immigration Promote the Investment of the Monopolistic Firm?

In the present paper, we examine the effect of increasing uncertainty of immigrants’ growth on the optimal timing of investment of a firm that has a monopolistic power over the labor market. It is revealed that when the uncertainty of immigrants’ growth is more than a threshold level, increasing uncertainty of immigrants’ growth accelerates the optimal timing of firms’ investment and enhances the economic growth, even if the uncertainty of immigrants’ growth is formulated by the geometric Brownian motion, which is in sharp contrast to the standard result that an increase in the uncertainty postpones the optimal timing. With an increase in the immigrants over the past ten years, workforces in the host countries have been growing significantly to the extent that the immigrants represent 70% of the increase in the workforce in Europe, and 47% in the United States as OECD indicates. In the present paper, we attempted to investigate the effect of increased uncertainty caused by the growi...

Education Policy Implementation: A Mechanism for Enhancing Primary Education Development in Zanzibar

Education is one of the fundamental rights of individuals; therefore, the government of a country needs to develop and strengthen educational policy and quality as well as to ensure that everyone has equal access to basic education. The improvement of access and quality of education in the world is becoming as an essential factor in development, whereas the basic education (primary school), is acknowledged as a foundation of the higher educational development for every country. To fulfill this goal, governments introduce several policies and procedures; however, it requires some reforms and participation from the politician, policymakers, and other stakeholders to re-examine educational policy so that it can lead to multiplication and betterment of the reforms. Educational reforms actually focus on accountability. A positive educational development and reform is very challenging and needs more effort and strategy on how to use and utilize the resources effectively as such it can achie...