in this paper, analysis of fluid flow and heat transfer over the bank of tubes is considered. k-ω sst model is applied for simulation of turbulent flow. in this paper, the improvement of efficiency of a bundle of circular tubes by changing the shape of the cross section of one row of the pipes to the elliptical cross section as an innovative plan is considered. as know, friction factor in turbu...

natural convective heat transfer of nano-fluid in porous media is present in many advanced engineering applications. in this work, this problem has been computationally simulated, using lbm. the configuration used includes a cold exterior region and hot interior cylinders with one-, two-, or three-cylinder arrangements. however, the effective area for heat transfer has been kept the same for al...

Centralized commercial refrigeration is becoming a sector where several technical options are competitive. These options are evaluated based on three major criterions: energy consumption, refrigerant emissions and initial cost. In supermarkets with machinery rooms, the competition is strong between previous centralized direct systems and new systems using heat transfer fluids. To achieve balanc...

Drying represents one of the oldest unit operations employed in industrial processes. Drying is viewed as a process of simultaneous heat and mass transfer. Porous Clay-like material undergoes stresses due to non-uniform distribution of temperature and moisture induced by heat and mass transfer respectively. The aim of this work is to simulate the stresses induced by heat and mass transfer durin...

Natural convection heat transfer was investigated experimentally in a concentric-cylinders annulus. To enhance the rate of heat transfer, pin fins were installed on the surface of the inner cylinder. Two fin arrangements were employed, namely, staggered and in-line arrangements. The length of the fins varied from 2 to 8 cm and the Rayleigh number Ra changed in the range from 5 x 105  to 5 x 106...

 Abstract: This paper presents the results of an experimental examination of the effect of non-uniform wall temperature on local heat transfer coefficient in a rotating smooth-walled square channel. Three different thermal boundary situations were investigated: (a) even and odd (four) wall uniform temperature, (b) even and odd (four) wall uniform heat flux, and (c) even (leading and trailing) w...

Fins are protrusions on a heat transfer surface to augment heat transfer rate from it. The increase in area exposed to convection in case of finned surfaces results in increased heat transfer rate. In this study heat transfer characteristics of a pin fin with perforation is numerically analyzed. A pin fin is fabricated and experiments are done under forced convection conditions. The experimenta...

A mathematical model of a continuous reheating furnace has been developed to identify the design and operating parameters that significantly affect furnace performance. In this study, the furnace is modeled 3 dimensionally and theMonte Carlomethod is used to find the overall absorption factor. The overall absorption factor is then used to calculate the energy balance for furnace walls, the gas,...

Recovery of both latent heat and condensate from boiler flue gas is significant for improving boiler efficiency and water conservation. The condensation experiments are carried out to investigate the simultaneous heat and mass transfer across the nanoporous ceramic membranes (NPCMs) which are treated to be hydrophilic and hydrophobic surfaces using the semicontinuous supercritical reactions. Th...

In this work, a Homotopy Perturbation Solution of magnetohydrodynamic (MHD) model of boundary-layer equations for an electrically conducting Nanofluid flow bounded by an infinite parallel vertical permeable plates is to be introduced. This model is applied to study the mass and heat transfer of an unsteady nanofluid, incompressible flow with suction, internal heat generation, Hall Effect and Ch...