جستجوی مقالات مرتبط با کلیدواژه « porous plate » در نشریات گروه « مکانیک »

In this research, the entropy generation by steady two-dimensional boundary layer flow of a hybrid nanofluid on a porous vertical flat plate with the magnetic field is studied. The governing equations by using of similarity solution transformed to nonlinear ordinary differential equations and also effect of buoyancy, magnetic, the volume fraction of nanofluid are investigated particularly on speed, temperature, and dimensionless entropy generation. The results showed that in entropy generation with an increase of similarity parameter, the thermal profile and absolute value of thermal gradient are decreased and therefore dimensional thermal entropy generation is decreased and trends to zero and after a certain amount thermal boundary layer is disappeared and just the entropy of fraction loss and magnetic field are produced. Also, the investigation shows with increasing density of nano particles, the speed of nanofluid decreases by about 30 percent and increases the thermal profile about 40 percent. The results also show with increase the magnetics, the speed of nanofluid decreases about 15 percent and decreases thermal profile about 10 percent.

In this paper, entropy generated during a continuous two-dimensional boundary layer flow on a porous flat plate surrounded by avariable heat flux is studied through a similarity solution. This study is presented for modeling of the cooling process of metalsurfaces with porous coating that is widely used in industry. Using similarity variables, the continuity, momentum,energyequations are transformed into ordinary differential equations. To validate the proposed solution, results are compared to the existingstudies. The effects of various parameters such as heat flux (q􀭵), suction parameter (S), Prandtl number (Pr), Stretch parameter onthe plate velocity (U), temperature distribution (T),dimensionless entropy (Ns) are shown,discussed in detail. Bijan numberis used as an important parameter for qualitative study in cooling process on porous surfaces. The increase of Bijan number isintroduced as a measure for the increase of cooling rate. The results of the study show that when Prandtl number increases, theentropy will decrease which leads to a decrease in Bijan number. However, an increase in permeability of surface causes toincreasing suction parameter,Bijan number.