this work concerns the peristaltic flow of a williamson fluid model in an inclined asymmetric channel under combined effects of heat and mass transfer. the governing nonlinear partial differential equations are simplified under the lubrication approach and then solved analytically and numerically. the analytical results are computed with the help of regular perturbation and the numerical result...

in recent years, impinging streams have received increasing interest for their high efficiency in heat and mass transfer. this numerical study was conducted to investigate flow and heat transfer characteristics of one-way opposing jets of non-newtonian fluids. effects of reynolds number impinging angle, momentum ratio and flow behavior index on mixing index were evaluated. the results showed im...

Experiments were conducted to determine the influence of local vapor quality on local heat transfer coefficient in flow boiling in an array of microchannels. Additionally, the variation of local heat transfer coefficient along the length and width of the microchannel heat sink for given operating conditions was investigated over a range of flow parameters. Each test piece includes a silicon par...

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...

Turbulent forced convective mass (heat) transfer downstream of blockages with round and elongated holes in a rectangular channel was studied. The blockages and the channel had the same 12:1 (width-to-height ratio) cross section, and a distance equal to twice the channel height separated consecutive blockages. The diameter of the holes was either 0.5 or 0.75 of the height of the channel. Naphtha...

This work concerns the peristaltic flow of a Williamson fluid model in an inclined asymmetric channel under combined effects of heat and mass transfer. The governing nonlinear partial differential equations are simplified under the lubrication approach and then solved analytically and numerically. The analytical results are computed with the help of regular perturbation and the numerical re...

Carbonation is one of the major deteriorations that accelerate steel corrosion in reinforced concrete structures. Many mathematical/numerical models of the carbonation process, primarily diffusion-reaction models, have been established to predict the carbonation depth. However, the mass transfer of carbon dioxide in porous concrete includes molecular diffusion and convection mass transfer. In p...

Experiments are conducted with a perfluorinated dielectric fluid, Fluorinert FC-77, to identify the critical geometric parameters that affect flow boiling heat transfer and flow patterns in microchannels. In recent work by the authors (Harirchian and Garimella IJMF 35:349-362, 2009), seven different silicon test pieces containing parallel microchannels of widths ranging from 100 μm to 5850 μm, ...

Roughness elements or turbulence promoters have been widely used to enhance heat transfer in cooling passages of modern gas turbine blades. Although such ribs substantially enhance heat transfer, the heat transfer coefficient is reduced immediately at corner downstream of each rib, creating hot spots. To remove such hot spots some of the ribs can be detached from the channel walls. In this pape...