An Investigation of Natural Convection in a Horizontal Concentric Annuli with Different Inner Shapes

Master of Science, Graduate Program in Mechanical Engineering
University of California, Riverside, August 2014
Dr. Kambiz Vafai, Chairperson

Abstract: An investigation of free convection in a horizontal concentric annuli with different inner shapes where the inner and outer surfaces are kept at a constant temperature is presented. The simulation is categorized into four groups based on the shape of the inner entity which can be either  cylindrical, elliptical,  square  or  triangular.  Flow  and  thermal fields are exhibited by means of streamlines and isotherms. Overall heat transfer correlations incorporating thermal radiation are established and presented  in  terms  of  the  Nusselt  numbers.  It  is  observed  that  the surface radiation and existence of the corners and larger top space can enhance the heat transfer rate. As the reference temperature increases, surface  radiation  plays  a  more prominent  role  in  the  overall  heat transfer performance.