Plate heat exchangers are widely used in industries due to their special characteristics, such as high thermal efficiency, small size, light weight, easy installation, maintenance, and cleaning. The purpose of this study is to consider the effect of depth, angle, and pitch of hemispheric Chevrons on the convective heat transfer coefficient and pressure drop. In the simulation of the heat ex...

conv hAs (Ts T ) where As is the heat transfer surface area and h is the convection heat transfer coefficient. When the temperatures Ts and T are fixed by design considerations, as is often the case, there are two ways to increase the rate of heat transfer: to increase the convection heat transfer coefficient h or to increase the surface area As. Increasing h may require the installation of a p...

in this work, the characteristics of flow and heat transfer of a fluid containing nano particles of aluminum oxide with the water volume fraction (0.1-0.2-0.3)(v/v) percent of the reports. the overall heat transfer coefficient, heat transfer and the average heat transfer fluid containing nano water - aluminum oxide in a horizontal double pipe counter flow heat exchanger under turbulent flow con...

Abstract It is well known that dropwise condensation (DWC) can achieve heat transfer coefficients (HTCs) up to 5-8 times higher as compared filmwise (FWC). The interaction between the condensing fluid and surface defines mode. Coatings present low energy high droplet mobility are a solution promote DWC instead of FWC on metallic substrates. In paper, effect vapor velocity during has been invest...

A theoretical model for nanofluid flow, including Brownian motion and thermophoresis, is developed and analysed. Standard boundary layer theory is used to evaluate the heat transfer coefficient near a flat surface. The model is almost identical to previous models for nanofluid flow which have predicted an increase in the heat transfer with increasing particle concentration. In contrast our work...

In this paper, conjugate heat transfer of magneto hydrodynamic mixed convection of nanofluid about a vertical slender hollow cylinder embedded in a porous medium with high porosity have been numerically studied. The Forchheimer’s modification of Darcy’s law was used in representing the nanofluid motion inside the porous media. The governing boundary layer equations were transformed to non-dimen...

Thermodynamic efficiency of the compression process in oil-flooded screw compressors depends greatly on the oil-gas heat transfer process. The amount of heat transfer is a function of many parameters such as mode of oil injection, oil inlet temperature, etc. This paper describes a mathematical model to calculate this heat transfer, assuming that the oil is injected in the form of non-interactin...

the objective of the present study is the synthesis of mwcnt-tio2 hybrid nanostructures by solvothermal synthesis method with ticl4 as precursor. the heat transfer enhancement due to the use of mwcnt-tio2 nanofluid was investigated. as-prepared hybrid materials were characterized by x-ray diffraction (xrd) and scanning electron microscopy (sem). the results showed that mwcnts were uniformly dec...

Heat sinks are widely adopted in electronics cooling together with different technologies to enhance the cooling process. For the small electronics application, the small scale pin fins heat sinks are extensively used to dissipate heat in electronics devices. Due to the limit of space in the small devices, it is impossible to increase heat transfer area. In order to improve the heat transfer pe...

in this paper, conjugate heat transfer of magneto hydrodynamic mixed convection of nanofluid about a vertical slender hollow cylinder embedded in a porous medium with high porosity have been numerically studied. the forchheimer’s modification of darcy’s law was used in representing the nanofluid motion inside the porous media. the governing boundary layer equations were transformed to non-dimen...