Effect of a moving plate on heat transfer in a uniform heat flux vertical channel

Abstract A numerical investigation of mixed convection in air due to the interaction between a buoyancy flow and the flow induced by a moving plate in a vertical channel is carried out. An adiabatic plate moves at a constant velocity in the mid-plane of the channel in the direction of the buoyancy force and the principal walls of the channel are heated at uniform heat flux. The effects of the channel aspect ratio, Rayleigh and Reynolds numbers are investigated and results in terms of the dimensionless channel wall and moving plate temperatures are given. Results show that the larger the channel aspect ratio, L / ( b / 2 ) , the stronger the effects of the moving plate. Increasing Reynolds number significantly decreases the dimensionless temperature of the channel walls. A composite correlation between Nusselt number and Reynolds and Richardson numbers is proposed in the range from natural convection to forced convection up to Re = 1.32 × 10 4 and 9.86 × 10 - 6 ⩽ Ri ⩽ 1.15 × 10 3 , for the channel aspect ratio in the [20.3–81.2] range.

[1]  Yogesh Jaluria,et al.  Thermal Processing of Materials: From Basic Research to Engineering , 2003 .

[2]  W. Aung Fully developed laminar free convection between vertical plates heated asymmetrically , 1972 .

[3]  R. J. Goldstein,et al.  Flow and heat transfer in the boundary layer on a continuous moving surface , 1967 .

[4]  Ali J. Chamkha,et al.  Effect of buoyancy forces on the flow and heat transfer over a continuous moving vertical or inclined surface , 2001 .

[5]  B. C. Sakiadis Boundary‐layer behavior on continuous solid surfaces: I. Boundary‐layer equations for two‐dimensional and axisymmetric flow , 1961 .

[6]  O. Manca,et al.  Composite correlations for air natural convection in tilted channels , 1999 .

[7]  B. Sundén,et al.  Computational Analysis of Convection Heat Transfer , 2000 .

[8]  B. C. Sakiadis Boundary‐layer behavior on continuous solid surfaces: II. The boundary layer on a continuous flat surface , 1961 .

[9]  C. H. Chen,et al.  Mixed convection cooling of a heated, continuously stretching surface , 2000 .

[10]  S. A. Al-Sanea,et al.  Convection regimes and heat transfer characteristics along a continuously moving heated vertical plate , 2003 .

[11]  T. Chen,et al.  Buoyancy Effects in Boundary Layers on Inclined, Continuous, Moving Sheets , 1980 .

[12]  C.-H. Chen,et al.  Laminar mixed convection adjacent to vertical, continuously stretching sheets , 1998 .

[13]  H.-T. Lin,et al.  Mixed convection from an isothermal vertical flat plate moving in parallel or reversely to a free stream , 1997 .

[14]  Y. Jaluria,et al.  Heat transfer from continuously moving material in channel flow for thermal processing , 1994 .