Abstract
In this study, entropy generation in laminar mixed convection in a square fluid-filled cavity is numerically studied. The middle of the lower wall of the cavity is heated to a constant temperature Th while the side-walls are maintained at a constant temperature Tc, and moving upper ward at a constant velocity to understand the effects of irreversibility distribution on the entropy generation for different engineering applications. For the studied control surface, remaining parts of lower and upper walls are adiabatic. The finite difference method is used to solve the governing equation. The entropy analysis is carried out to determine the irreversibility which is generated in the cavity for different Prandtl number (Pr=0.0212, 0.71 and 6.35), the effect of the irreversibility distribution ratio on entropy generation was investigated. It seen that effect of irreversibility distribution ratio (γ=10-2 and 10-4) have play important role on the total entropy for different Prandtl number. Also it is clear that, for all Prandtl number, the total entropy generation increase by increasing the irreversibility distribution ratio and the increase of Prandtl number regardless the values of Ri=1 and Re=100 because of the increase of the velocity gradients.
Highlights
Flow and heat transfer in different cavities have a wide range of applications in the engineering devices and industry, such as: the solar energy system, cooling systems producing nuclear energy, chemical and electronic devices and heat exchangers etc [1,2,3]
The study of entropy generation has been initiated by Bejan [3], which considers that the entropy generation of fluid flow under forced and laminar convection is induced by viscous and thermal mechanisms, predicting velocity and temperature gradients
Yilbas et al [4] presented a numerical study of the entropy generation in natural convection and laminar flow in a square cavity with bottom-heated, topdown and vertical walls adiabatic
Summary
Flow and heat transfer in different cavities have a wide range of applications in the engineering devices and industry, such as: the solar energy system, cooling systems producing nuclear energy, chemical and electronic devices and heat exchangers etc [1,2,3]. Due to its uttermost importance, many applications, many researches, investigations and studies have been created to raise the performance and quality of those engineering systems Among these studies is the study of the entropy generation. Yilbas et al [4] presented a numerical study of the entropy generation in natural convection and laminar flow in a square cavity with bottom-heated, topdown and vertical walls adiabatic. Nine cases were studied by varying the difference of temperature between the hot wall and the cold wall (the Rayleigh number (Ra) varies between 1.36 105 and 3.96 105) They found that entropy generation increases as the velocity of flow in the horizontal direction increases.
Sign-in/Register to view highlights & summary 
Published Version
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call