Numerical Study of the Mass Transfer Effects on the Flow and Thermal Fields Structures under the Influence of Natural Convection

Document Type : Research Article


Department of Mechanical Engineering, University of Qom


In this paper, a numerical study has been carried out for coupled mass, momentum and heat transfer in the field under effects of natural convection. For this purpose, the unsteady incompressible Navier-Stokes equations with the terms of the Buoyancy forces (due to temperature gradients), energy conservation and concentration (mass) transfer equations have been simultaneously solved using appropriate numerical methods. In order to discretize spatial terms, a combined formulation contains a second-order central difference method and the first-order upwind scheme has been used. Time integration of the governing equation has been performed using the fourth order Runge-Kutta method. The effect of variations of the mass of contaminant has been studied in changing the flow and thermal fields structure. It is concluded from obtained results, an increase in mass flow rate of secondary (mass) injection, alters the structure of the flow and thermal fields. Comparison of the results obtained from the numerical model with appropriate reference data shown that the model has relatively good accuracy.


dor 20.1001.1.25882953.2019.

Main Subjects

[1] B. LC., Convective heat transfer, second edition ed., John Wiley & Sons, New York, 1993.
[2] W.M. Kays, C. M.E., Convective heat and mass transfer, Third edition ed., McGraw-Hill, New York, 1993.
[3] B. A., Convection heat transfer, Fourth edition ed., John Wiley & Sons, New York, 2013.
[4] A. Guha, K. Pradhan, A unified integral theory of laminar natural convection over surfaces at arbitrary inclination from horizontal to vertical, International Journal of Thermal Sciences, 111 (2017) 475- 490.
[5] X. Shi, J. Khodadadi, X. Hai, Laminar Natural Convection in a Square Cavity Due to an Oscillating Thin Fin: Transient Behavior, in: 9th AIAA/ ASME Joint Thermophysics and Heat Transfer Conference, 2006, pp. 3094.
[6] M. Hasnaoui, E. Bilgen, P. Vasseur, Natural convection heat transfer in rectangular cavities partially heated from below, Journal of Thermophysics and Heat transfer, 6(2) (1992) 255-264.
[7] P. Oosthuizen, J. Paul, Natural convection in a rectangular enclosure with three heated sections on the lower surface, in: 38th AIAA Thermophysics Conference, 2005, pp. 4825.
[8] M.R. Haque, A.R. Betz, Numerical Study of Natural Convection Heat Transfer Over a Cooling Stage, in: ASME 2017 International Mechanical Engineering Congress and Exposition, American Society of Mechanical Engineers Digital Collection, 2017.
[9] H. Tao, L. Qingxuan, T. Peng, Numerical simulation of natural convection in a three-dimensional hermetic cavity, in: 2017 International Conference on Advanced Mechatronic Systems (ICAMechS), IEEE, 2017, pp. 123-130.
[10]H.-S. Dou, G. Jiang, Numerical simulation of flow instability and heat transfer of natural convection in a differentially heated cavity, International Journal of Heat and Mass Transfer, 103 (2016) 370-381.
[11]J.R. Lee, Numerical simulation of natural convection in a horizontal enclosure: Part I. On the effect of adiabatic obstacle in middle, International Journal of Heat and Mass Transfer, 124 (2018) 220-232.
[12] S. Yildiz, B. Ba┼čaran, Investigation of Natural Convection Heat Transfer Along a Uniformly Heated Vertical Plate, Arabian Journal for Science and Engineering, 44(2) (2019) 1685-1696.
[13]A. Taymourtashm, M. Ebrahimi, M. Rafei, Natural Convection on a Vertical Non-Isothermal Plate in a Supercritical Fluid, in: Proceeding of the 16th Iranian Society of Mechanical Engineers (ISME) Conference, ISME, Kerman, Iran 2008.
[14]M. M.K, Numerical Simulation of Fluid Flow and Transfer of Pollutants in a Field under the Influence of Natural Convection, in: Proc. of the 6th Conference on Application of CFD in Chemical and Petrulem Industries, Isfahan, Iran, 2015.
[15]M. M.K, Reduced Order Modeling of Mass, Momentum and Energy Transfer in a Field under the Influence of Temperature Gradient Based on Proper Orthogonal Decomposition, in: Proc. of the 7th Conference on Application of CFD in Chemical and Petrulem Industries, Kerman, Iran 2016.
[16]K.A. Hoffmann, and Chiang, S. T., Computational fluid dynamics, Engineering Education System Publications 2000.
[17]D. Venturi, On proper orthogonal decomposition of randomly perturbed fields with applications to flow past a cylinder and natural convection over a horizontal plate, Journal of Fluid Mechanics, 559 (2006) 215.