Abstract. — Einstein’s Doppler formula is not applicable when a moving point light source is close enough to the observer; for example, it may break down or cannot specify a determinate value when the point source and the observer overlap. In this paper, Doppler effect for a moving point light source is analyzed, and it is found that the principle of relativity allows the existence of intrinsic...

In this work a numerical investigation of transient temperature profile of laser beam welding process is carried out. A 3-D finite element modelling isdevelopedconsidering combined double-ellipsoidalheat source model for both spot and moving heat source. The temperature dependent thermo-physical material property of Ti-6Al-4V alloy isincorporated. The effect of latent heat of fusion and convect...

This paper presents an analytical solution of the hyperbolic heat conduction equation for moving semi-infinite medium under the effect of time dependent laser heat source. Laser heating is modeled as an internal heat source, whose capacity is given by g x, t I t 1 − R μe−μx while the semi-infinite body has insulated boundary. The solution is obtained by Laplace transforms method, and the discus...

Transient thermal field in laser surface hardening treatment of medium carbon steel was analyzed by employing both three-dimensional analytical model and finite element model. In finite element model the laser beam was considered as a moving plane heat flux to establish the temperature rise distribution in the work-piece, while in analytical model laser beam was considered as an internal heat s...

Free convection effects and heat transfer due to a pulsating point heat source embedded in an infinite, fluid saturated, porous dusty medium are studied analytically. Both velocity and temperature fields are discussed in the form of series expansions in the Rayleigh number, for both the fluid and particle phases based on the mean heat generation rate from source and on the permeability of the p...

In this paper a laminar flow of water on an ice layer subjected to a slip condition is considered numerically. The paper describes a parametric mathematical model to simulate the coupled heat and mass transfer events occurring in moving boundary problems associated with a quasi steady state steady flow process. The discretization technique of the elliptic governing differential equations of mas...

Numerous liver cancer oncologists suggest bridging therapies to limit growth until donors are available. Interventional radiology including radiofrequency ablation (RFA) is one such therapy. This locoregional therapy aims produce an optimal amount of heat kill cells, where the produced by a (RF) needle. Less experienced Radiologists (IRs) require software-assisted smart solution predict distrib...