high temperatures are often encountered in almost all of the combustion systems, therefore, thermal radiation heat transfer can influence the droplets heat up rate and consequently their life time. in this paper, the effect of thermal radiation heat transfer is investigated for two cases of directional and spherically symmetric illuminations. the flow and temperature fields insdie and outside o...

using of nanofluids and ducts with corrugated walls are both supposed to enhance heat transfer, by increasing the heat transfer fluid conductivity and the heat transfer area respectively. use of a diverging duct with a jet at inlet section may further increase heat transfer by creating recirculation zones inside the duct. in this work two-dimensional incompressible laminar flow of a nanofluid e...

in this paper, a three-dimensional finite element model has been developed to simulate the laser-tig hybrid welding (hlaw) of stainless steel 1.4418 with thickness of 4 mm. transient temperature profile and dimensions of the fusion zone and heat affected zone (haz) during welding process are calculatedusing finite element method (fem) and were solved in the abaqus/standard software.the heat sou...

in order to examine the laminar convective heat transfer of nanofluid, experiments carried out using silver-oil nanofluid in a concentric annulus with outer constant heat flux as boundary condition. silver-oil nanofluid prepared by electrical explosion of wire technique and observed no nanoparticles agglomeration during nanofluid preparation process and carried out experiments. the average size...

heat stress is a common occupational health hazard at outdoor workplaces especially in a hot-humid climate. overheating of the body can cause a number of problems, including heat rash, heat cramps, dizziness, heat exhaustion, and heat stroke. the present study aimed to assess heat stress indices including di, wbgt, and sw req /phs, as a mean to estimate the heat load on the employees of a petro...

Heat transfer coefficient in nucleate pool boiling near critical heat flux at least one orderhigher than the convectional heat transfer modes. In this paper, an experimental setup isdesigned and fabricated to investigate the mechanism of heat transfer from boiling surface tobulk liquid near critical heat flux. The images of pool boiling near the high heat flux regionreveals that the individual ...

in the presented research, heat transfer of a mobile electrolyte alkaline fuel cell (afc) (which the electrolyte has cooling role of system) has been considered. proper control volumes of system with specific qualification have been chosen. consequently, heat and mass transfer in control volumes have been assessed. considerations on them and contributed models lead to approve a double tube heat...

In this paper, the cooling performance of water-cooled heat sinks for heat dissipation from electronic components is investigated numerically. Computational Fluid Dynamics (CFD) simulations are carried out to study the rectangular and circular cross-sectional shaped heat sinks. The sectional geometry of channels affects the flow and heat transfer characteristics of minichannel heat sinks. T...

Helical coil heat exchangers are widely used in industrial applications ranging fromcryogenic processes, air-conditioning, and nuclear reactors to waste heat recovery due totheir compact size and high heat transfer coefficient. In this kind of heat exchangers, flowand heat transfer are complicated. This paper reports a numerical investigation of theinfluence of different parameters such as coil...

Experimental investigations has been done to find out the heat transfer characteristics and friction factor of water based Al2O3 nanofluids as a coolant in  brazed plate heat exchanger. Plate heat exchanger either use horizontally or vertically. The base plate of the plate heat exchanger was kept inclined at (0⁰, 30⁰ ,60⁰, 90⁰). The experimentation have been done on the two different concentrat...