in this paper, experimentally derived correlations of heat transfer and pressure drop are used in a pareto based multi-objective optimization (moo) approach to find the best possible combinations of heat transfer and pressure drop of tio2-water nanofluid flow in tubes fitted with multiple twisted tape inserts in different arrangement. in this study there are four independent design variables: t...

An analytical study was performed to study effects of thermo-diffusion and chemical reactions on a three-dimensional MHD mixed convective flow of dissipative fluid along an infinite vertical porous plate with transverse sinusoidal suction velocity. The parabolic partial differential equations governing the fluid flow, heat transfer, and mass transfer were solved using perturbation technique and...

There are a number of systems in which supercritical cryogenic fluids are used as coolants or propellant fluids. In some modern military aircraft, the fuel is pressurized above its critical point and used as a coolant to remove heat from the aircraft engine. Accurate prediction of heat transfer coefficients to turbulent flows of supercritical fluids is essential in design of such systems. One o...

There are heat losses during the cycle of real engine that are neglected in ideal air-standard analysis. In this paper, the effect of heat transfer on the net output work is shown and thermal efficiency of the air-standard Atkinson and the Dual combustion cycles are analyzed. Comparison of performances of the air-standard Atkinson and the Dual combustion cycles with heat transfer considerations...

In this paper, fluid flow and heat transfer in the laboratory (small size) shell tube heat exchanger are analysed by computational fluid dynamic software. In this type of shell tube heat exchanger baffles with different angles of rotation: 00 (horizontal segmental baffle), 150 (from horizontal), 300, 450, 600, 750, 900 (vertical segmental baffle) is used. Effect of baffle orientation on shell t...

Heat transfer is investigated on three levels of description: Fourier, Cattaneo, and Peierls. The microscopic nature of the heat that becomes important, in particular in nanoscale systems, is characterized by a vector field related to the heat flux on the Cattaneo level and by the phonon distribution function on the Peierls level. All dynamical theories discussed in the paper are fully nonlinea...

In this article, a time dependent partial differential equation is used to model the nonlinear boundary value problem describing heat transfer through a radial porous moving fin with rectangular profile. The study is performed by applying a numerical solver in MATLAB (pdepe), which is a centered finite difference scheme. The thermal conductivity and fin surface emissivity are linearly ...

In internal combustion engines, exhaust valve and its seat gain considerable temperature as the hot gases exit through them. So, the rate of heat transfer should be under control. In this study, the contact heat transfer coefficient has been estimated. An experimental study on an Air-Cooled internal combustion engine cylinder head has been considered. Using the measured temperatures of sensors ...

in this study, thermal performance of a cylindrical heat pipe is investigated numerically. three different types of water based nanofluids, namely (al2o3+water), (diamond+water) and (multi-wall carbon nano tube (mwcnt) +water) have been used. the influence of using the simple nanofluids and mwcnt nanofluid on the heat pipe characteristics such as liquid velocity, pressure profile, temperature p...

The lattice Boltzmann method (LBM) was used to analyze two-dimensional (2D) non-Fourier heat conduction with temperature-dependent thermal conductivity. To this end, the evolution of wave-like temperature distributions in a 2D plate was obtained. The temperature distributions along certain parts of the plate, which was subjected to heat generation and constant thermal conductivity condit...