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 present study, the two phase flow boiling heat transfer coefficient and pressure drop of R410A, R32 and R290 in microchannels are demonstrated. The experimental data were conducted in horizontal stainless steel tubes with the inner diameter of 0.3 mm and 1.5 mm. The testing conditions were performed with the mass fluxes range from 200 to 500 kg/m2s, the heat fluxes from 10 to 20 kW/m2, the s...

In this study, the convective heat transfer and pressure drop in laminar flow of Al2O3/water and CuO/water nanofluids through square and triangular cross-sectional ducts have been numerically investigated using new technique. It has been assumed that there is constant heat flux boundary condition at walls. In addition, to include the presence of nanoparticles, the dispersion model has been used...

Bubble columns are gas- liquid contactors that are widely used in chemical and bio- chemical industries. High mixing that result in high heat and mass transfer rates are amongst their advantages. Heat transfer in a bubble column having a bundle of heaters investigated and the variation of heat transfer coefficient with variation in heaters pitch to diameter ratios in a bundle of heaters reporte...

The ozonation of synthetic wastewater containing azo dye Acid Red 14 (AR 14) was investigated in a high-throughput microporous tube-in-tube microchannel reactor. The effects of design and operating parameters such as micropore size, annular channel width, liquid volumetric flow rate, ozone-containing gas volumetric flow rate, initial pH of the solution and initial AR 14 concentration on decolor...

The objective of this study was to investigate the hydrodynamics and gas-liquid mass transfer coefficient an external-loop airlift reactor (ELAR). ELAR operated in three cases: different inlet velocities fluids, alcohols solutions (water, 0.5% methanol, ethanol, propanol butanol) concentration methanol (0%, 0.5%, 1%, 2% 5%). influence superficial gas velocity various diluted alcohol on studied....

Effect of configuration (structure of electrode, interelectrode gap, positions of inlet and outlet, volume of the cell and additional nets) on mass transfer characteristic of a filter-press type electrochemical cell has been studied. The mass transfer coefficients on the electrodes were obtained by using the well-known technique based on the determination of limiting diffusion current. It is fo...

A mass transfer model is proposed for prediction of permeate concentration and percent rejection at different inlet pressures and feed dye concentrations in membrane ultrafiltration. A differential equation in cylindrical co-ordinates considering the spiral wound membrane equivalent to a cylindrical module is derived which coupled with mass balance and permeate flux equations are solved to yiel...