Numerical analysis of 3D cross flow between corrugated parallel plates in evaporative coolers

Steady state laminar 3D cross flow, between two sinusoidal corrugated parallel plates, with perpendicular directions of corrugation is modeled in the present work. The velocity field is assumed to be periodic across each wave but the thermal field is assumed to be developing. The results are studied as thermal development and effect of the number of waves along the flow direction on bulk temperature and saturation efficiency, due to different Reynolds numbers, when Prandtl number is 0.7. Saturation efficiency increases with increase in the number of waves along media depth, and decreases when Reynolds number or the amplitude to wavelength ratio grows. There is a specific length of media depth in each geometrical aspect ratio and Reynolds number, which can satisfy any specific saturation efficiency. With respect to relations between desired relative humidity and saturation efficiency, in different residential, agricultural or industrial applications, the proper size of the domain or Reynolds number, can be estimated through the resulted diagrams. Respectively, further number of waves along media, follows unwanted additional pressure drop and waste of energy and material.

[1]  K. Sumathy,et al.  Theoretical study on a cross-flow direct evaporative cooler using honeycomb paper as packing material , 2002 .

[2]  S. Vanka,et al.  Convective heat transfer in periodic wavy passages , 1995 .

[3]  Reza Hosseini,et al.  Numerical modeling of rigid media evaporative cooler , 2006 .

[4]  Enrico Nobile,et al.  Numerical analysis of fluid flow and heat transfer in periodic wavy channels , 2001 .

[5]  R Poulter,et al.  Hydrodynamics and thermal characteristics of corrugated channels: computational approach , 2000 .

[6]  Huang Xiang,et al.  Theoretical analysis on heat and mass transfer in a direct evaporative cooler , 2009 .

[7]  Nishimura Tatsuo,et al.  Flow observations and mass transfer characteristics in symmetrical wavy-walled channels at moderate Reynolds numbers for steady flow , 1990 .

[8]  Yasar Islamoglu,et al.  The effect of channel height on the enhanced heat transfer characteristics in a corrugated heat exchanger channel , 2003 .

[9]  R. M. Manglik,et al.  Effect of fin waviness and spacing on the lateral vortex structure and laminar heat transfer in wavy-plate-fin cores , 2004 .

[10]  W. Worek,et al.  Heat transfer and pressure drop properties of high viscous solutions in plate heat exchangers , 2008 .

[11]  William M. Worek,et al.  THE EFFECT OF LONGITUDINAL HEAT CONDUCTION IN CROSS FLOW INDIRECT EVAPORATIVE AIR COOLERS , 2007 .

[12]  S. Mahmud,et al.  Separation characteristics of fluid flow inside two parallel plates with wavy surface , 2002 .

[13]  R. M. Manglik,et al.  Enhanced heat transfer due to curvature-induced lateral vortices in laminar flows in sinusoidal corrugated-plate channels , 2004 .

[14]  Madjid Soltani,et al.  Performance improvement of gas turbines of Fars (Iran) combined cycle power plant by intake air cooling using a media evaporative cooler , 2007 .

[15]  A. Chorin.  A Numerical Method for Solving Incompressible Viscous Flow Problems , 1997 .

[16]  Raj M. Manglik,et al.  Low Reynolds number forced convection in three-dimensional wavy-plate-fin compact channels: fin density effects , 2005 .

[17]  Hua Zhang,et al.  NUMERICAL INVESTIGATION ON THE HEAT AND MASS TRANSFER IN A DIRECT EVAPORATIVE COOLER , 2009 .