Heat and Mass Transfer
Pooja Sharma; Tarun Sharma; Navin Kumar
Abstract
Entropy generation due to viscous incompressible MHD forced convective dissipative fluid flow through a horizontal channel of finite depth in the existence of an inclined magnetic field and heat source effect has been examined. The governing non-linear partial differential equations for momentum, energy ...
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Entropy generation due to viscous incompressible MHD forced convective dissipative fluid flow through a horizontal channel of finite depth in the existence of an inclined magnetic field and heat source effect has been examined. The governing non-linear partial differential equations for momentum, energy and entropy generation are derived and solved by using the analytical method. In addition; the skin friction coefficient and Nusselt number are calculated numerically and their values are presented through the tables for the upper and the bottom wall of the channel. It was concluded that; total entropy generation rate and Bejan number are reduced due to rise in the inclination angle of the magnetic field. Also, an increment in the heat source prop ups the fluid temperature and total entropy generation rate. This study will help to reduce the energy loss due to reversible process and heat dissipation. The results are very useful for chemical and metallurgy industries.
Perturbation Technique
Abbas Kosarineia
Abstract
The entropy generation analysis of non-Newtonian fluid in rotational flow between two concentric cylinders is examined when the outer cylinder is fixed and the inner cylinder is revolved with a constant angular speed. The viscosity of non-Newtonian fluid is considered at the same time interdependent ...
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The entropy generation analysis of non-Newtonian fluid in rotational flow between two concentric cylinders is examined when the outer cylinder is fixed and the inner cylinder is revolved with a constant angular speed. The viscosity of non-Newtonian fluid is considered at the same time interdependent on temperature and shear rate. The Nahme law and Carreau equation are used to modeling dependence of viscosity on temperature and shear rate, respectively. The viscous dissipation term is adding elaboration to the formerly highly associate set of governing motion and energy equations. The perturbation method has been applied for the highly nonlinear governing equations of base flow and found an approximate solution for narrowed gap limit. The effect of characteristic parameter such as Brinkman number and Deborah number on the entropy generation analysis is investigated. The overall entropy generation number decays in the radial direction from rotating inner cylinder to stationary outer cylinder. The results show that overall rate of entropy generation enhances within flow domain as increasing in Brinkman number. It, however, declines with enhancing Deborah number. The reason for this is very clear, the pseudo plastic fluid between concentric cylinders is heated as Brinkman number increases due to frictional dissipation and it is cooled as Deborah number increases which is due to the elasticity behavior of the fluid. Therefore, to minimize entropy need to be controlled Brinkman number and Deborah number.
Heat and Mass Transfer
Majid Kerdarian; Ehsan Kianpour
Abstract
In this study, the finite volume method and the SIMPLER algorithm is employed to investigate forced convection and entropy generation of Cu-water nanofluid in a parallel plate microchannel. There are four obstacles through the microchannel, and the slip velocity and temperature jump boundary conditions ...
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In this study, the finite volume method and the SIMPLER algorithm is employed to investigate forced convection and entropy generation of Cu-water nanofluid in a parallel plate microchannel. There are four obstacles through the microchannel, and the slip velocity and temperature jump boundary conditions are considered in the governing equations to increase the accuracy of modeling. The study is conducted for the Reynolds numbers in the range of 0.1<Re<10, Knudsen numbers ranging of 0<Kn<0.1, and volume fraction of nanoparticles ranging of 0<φ