In this paper the heat transfer characteristics of a two-phase closed thermosyphon over a wide range of heat transfer rates, system pressure, aspect ratios and filling ratios were studied. The experiments focused on the boiling and condensation heat transfer characteristics of the thermosyphon. The experimental boiling and condensation heat transfer coefficients inside the thermosyphon were com...

obtaining temperature distribution data of slabs under rolling is essential as the mechanical and metallurgical properties of the metal under this process vary with temperature. using the control volume method, a mathematical model is employed in this study to predict slab temperature in the hot roll process at mobarakeh steel company. the effects of different parameters including the heat resu...

In this article, the author has used fractional calculus to explain the wave nature of heat propagation as well as heat conduction at molecular level with dual phase lag; in this row he proposed dual phase lag heat equation of fractional order. Modified Adomian Decomposition Method and New Iterative Method are applied to obtain the approximate analytical solutions of the proposed model. Numeric...

Heat propagation in the Guyer–Krumhansl model is studied. The exact analytical solutions for the one-dimensional Guyer–Krumhansl equation are obtained. The operational formalism is employed. Some examples of initial functions are considered, modeling various initial heat pulses and distributions. The effect of the ballistic heat transfer in an over–diffusive regime is elucidated. The behavior o...

The convective-diffusion equation is the governing equation of many important transport phenomena in building physics. The paper deals in its first part with the general formulation of the convective-diffusion equation and with the numerical solution of this equation by means of the finite element method. The second part of the paper contains the analysis of one typical combined transport probl...

An optimal control problem for a nonlinear steady-state heat transfer model accounting for heat radiation effects is considered. The problem consists in minimization of a given cost functional by controlling the sources in the heat equation. The solvability of this control problem is proved, optimality conditions are derived, and an iterative algorithm for solving the optimal control problem is...

In this work, the characteristics of flow and heat transfer of a fluid containing nano particles of aluminum oxide with the water volume fraction (0.1-0.2-0.3)(V/V) percent of the reports. The overall heat transfer coefficient, heat transfer and the average heat transfer fluid containing nano water - aluminum oxide in a horizontal double pipe counter flow heat exchanger under turbulent flow con...

Modelling of building heat transfer needs two basic material characteristics: heat conduction factor and thermal capacity. Under some simplifications these two factors can be determined from a rather simple equipment, generating heat from one of two aluminium plates into the material sample and recording temperature on the contacts between the sample and the plates. However, the numerical evalu...

Abstract Heat transfer in skin tissue is an area of interest for medical sciences. In this paper we intend to study fractional bioheat equation for heat transfer in skin tissue with constant and sinusoidal heat flux condition on skin surface. Numerical solutions are obtained by implicit finite difference method. We study the effect of anomalous diffusion in skin tissue and compare it with norma...