in this paper, a three-dimensional finite element model has been developed to simulate the laser-tig hybrid welding (hlaw) of stainless steel 1.4418 with thickness of 4 mm. transient temperature profile and dimensions of the fusion zone and heat affected zone (haz) during welding process are calculatedusing finite element method (fem) and were solved in the abaqus/standard software.the heat sou...

in this paper the optimal control of boundary heat flux in a 2-d solid body with an arbitrary shape is performed in order to achieve the desired temperature distribution at a given time interval. the boundary of the body is subdivided into a number of components. on each component a time-dependent heat flux is applied which is independent of the others. since the thermophysical properties are t...

We sketch a rigorous derivation of Fourier's law from a system of closure equations for a nonequilibrium stationary state of a Hamiltonian system of coupled oscillators subjected to heat baths on the boundary. The local heat flux is proportional to the temperature gradient with a temperature dependent heat conductivity and the stationary temperature exhibits a nonlinear profile.

An optothermal analyte preconcentration method is introduced in this work based on temperature gradient focusing. The present approach offers a flexible, noncontact technique for focusing and transporting of analytes. Here, we use a commercial video projector and an optical system to generate heat and control the heat source position, size and power. This heater is used to focus a sample model ...

A theory is presented for the evaluation of the different terms of the pressure gradient force, when mesoscale flow is driven by a sensible heat source in the planetary boundary layer (PBL), or by an elevated confined heat source, such as the release of the latent heat of condensation in a cloud. The nonlinear and linear, and the nonhydrostatic and the hydrostatic pressure gradient contribution...

The Na(+),K(+)-ATPase is accepted as an important source of heat generation (thermogenesis) in animals. Based on information gained on the kinetics of the enzyme's partial reactions we consider via computer simulation whether modifications to the function of the combined Na(+),K(+)-ATPase/plasma membrane complex system could lead to an increased body temperature, either through the course of ev...

Fourier theory of thermal transport considers heat transport as a diffusive process where energy flow is driven by a temperature gradient. However, this is not valid at length scales smaller than the mean free path for the energy carriers in a material, which can be hundreds of nanometres in crystalline materials at room temperature. In this case, heat flow will become 'ballistic'--driven by di...

Charge transport and chemical reactions during charging and discharging of a battery produce heat that determines temperature behaviors. The elevated temperature causes undesired side reactions that accelerate degradation and potentially result in catastrophic operating conditions like a thermal runaway. The heat generated in an operating battery is generally approximated by the sum of the reve...

This paper modeled heating air of a room through examining free convection in a 3D chamber. The chamber had cold and hot sources with Tc and Th temperatures, respectively. Its other walls were adiabatic. This study aimed at predicting effect of temperature difference, displacement of hot and cold sources and their aspect ratio on flow field, temperature and heat transfer rate. To conduct the st...