In this work, inorganic fouling of the heat transfer surfaces from potable water has been studied using a once-through flow cell to visualize and follow deposition processes. The effects surface material rate on amount morphology deposits have investigated. scale which formed mainly consists two distinct regions; smooth flat layer rough calcium carbonate layer. It also revealed that scaling ten...

The CFD simulation of heat transfer characteristics of a nanofluid in a circular tube under constant heat flux was considered using Fluent software (version 6.3.26) in the laminar flow. Al2O3 nanoparticles in water with concentrations of 0.5%, 1.0%, 1.5%, 2% and 2.5% were used in this simulation. All of the thermo-physical properties of nanofluids were assumed to be temperature independent. Two...

Convective heat transfer about an isothermal, cylindrical extrudate of constant diameter, issuing continuously from an extrusion die, is investigated numerically, using a commercial CFD software package. The hot extrudate is assumed to move vertically downward, thus giving rise to a combined regime of forced and free convection in the surrounding fluid. Prandtl number of 0.707, corresponding to...

Heat transfer in rough circular cylinder microfins is studied and a new analytical model is developed. Assuming Gaussian isotropic surface roughness, it is shown that both cross-sectional and surface areas ofmicrofins increase by increasing roughness. Consequently, an enhancement is observed in the heat transfer rate and thermal performance of microfins. The effect of roughness is more profound...

In this paper we discuss the effect of chemical reaction and thermal radiation on unsteady free convective heat and mass transfer flow through a porous medium in a vertical wavy channel. The unsteadiness in the flow is due to the oscillatory flux in the flow region. The coupled equations governing the flow, heat and mass transfer have been solved by using a perturbation technique with the slope...

A generalized analytical solution to the set of coupled energy balance equations governing heat transfer in a system comprised of uniform radius spherical particles, with nonuniform initial temperature, heated in a well mixed liquid with time varying temperature, is initially derived. Based on this solution, analytical equations describing the temperature evolution for both fluid and particles,...

Experimental data was generated by performing the experiment on a plate heat exchanger for water/water system, at different flow rate and different hot water inlet temperature, at steady state conditions. Overall heat transfer coefficient (U) is determined for the performance evaluation of plate heat exchanger. The thermal properties of water (thermal Conductivity, Specific heat and density) at...

This paper develops convective heat transfer coefficients for several different BIPV/T system configurations using Computational Fluid Dynamics models. The results for one of the CFD cases are validated with experimental data from a BIPV/T installation. The second part of the paper describes a model which is used to generate annual performance data for the system, including thermal and electric...

Heatlines were proposed in 1983 by Kimura and Bejan (1983) as adequate tools for visualization and analysis of convection heat transfer. The masslines, their equivalent to apply to convection mass transfer, were proposed in 1987 by Trevisan and Bejan. These visualization and analysis tools proved to be useful, and their application in the fields of convective heat and/or mass transfer is still ...