In this study, the relationship among the concepts of entropy generation rate, entransy theory, and generalized thermal resistance to the optimal design of thermal systems is discussed. The equations of entropy and entransy rates are compared and their implications for optimization of conductive heat transfer are analyzed. The theoretical analyses show that based on entropy generation minimizat...

this paper presents results of a numerical study of mixed convection and entropy generation of cu–water nanofluid in a square ventilating cavity at different inclination angles. except a piece of bottom wall with a uniform heat flux, all of the cavity walls are insulated. the inlet port is placed at the bottom of the left wall and the outlet port is positioned at the top of the right wall. entr...

The theory of available potential energy applied to a “translating” atmospheric volume is used to estimate the generation of available potential energy for the cyclogenetic, mature, and occluding stages of a mid-latitude cyclone. Primary attention is focused upon the importance of the diabatic process of latent heat release in generating the storm’s available potential energy. In addition, prel...

Nowadays, precise prediction of heat generation in semiconductor devices is important. An electro-thermal analysis is an attractive method to predict heat generation in devices. In this analysis, momentum and energy relaxation times are taken as the important parameters. Calculated heat generation density is dependent on the energy relaxation time. Conventionally, these relaxation times have be...

The heat transfer for a non-Newtonian power-law fluid over a moving surface is investigated by applying a uniform suction/injection velocity profile. The flow is influenced by internal heat generation/absorption. The energy equation is solved at constant surface temperature condition. The Merk-Chao series is applied to obtain a set of ODEs instead of a complicated PDE. The converted ordinary diffe...

The influence of self-heating by power dissipation on the operation of semiconductor devices proves to be important not only in the area of power electronics, but also for VLSI devices. Hence, besides the carrier densities (or quasi-Fermi potentials, alternatively), temperature has to be included as additional dynamic state variable in the simulation of the electric and thermal behavior of such...

Fuel flexibility is a significant advantage of solid oxide fuel cells (SOFCs) and can be attributed to their high operating temperature. The eligibility of a combined heat and power (CHP) system has been investigated as a new power generation methode, in this study. Natural gas fueled SOFC power systems via methane steam reforming (MSR) yield electrical conversion efficiencies exceeding 50% and...

 The forced convection heat transfer of turbulent Al2O3-water nanofluid flow inside the grooved tubeswith the different aspect ratio of the rectangular grooves is numerically investigated. The governingequations have been solved using finite volume method (FVM) coupled with SIMPLE algorithm. It isassumed the heat flux is constant on the grooved walls. The Single-phase approach is applied for th...