scholarly journals Numerical study of the effect of a surface active agent on convective mass transfer in laser surface melting of metal

2012 ◽  
Vol 5 (2) ◽  
pp. 253-258
Author(s):  
V.N. Popov
Author(s):  
Utsavkumar Mistry ◽  
Madhu Vadali

Abstract Pulsed Laser Surface Melting (pLSM) is a technique that offers an efficient way to modify the geometry surfaces without any addition or removal of material. In pLSM, an incident laser beam melts a small region on the surface and induces surface tension and viscosity-driven flows that modify the surface geometry. Initial surface geometry plays an important role in deciding the melt pool flows and shape as it governs the initial surface tension acting on the melt pool. In this paper, we present a systematic numerical study that captures the effects of initial geometries using a two-dimensional axisymmetric model. The results show that geometries with higher curvatures result in deeper melt pools and higher surface displacement because higher fluid velocities aid the convection heat transfer. Additionally, we define a modified capillary number (CaM) which elegantly captures these effects.


2011 ◽  
Vol 52-54 ◽  
pp. 1879-1883
Author(s):  
Yun Guo

The paper focuses on the enhancement of heat and mass transfer by adding active agent to lithium bromide aqueous solution. Through absorption experiments with local optical measurement, the qualitative analysis of the causes of the absorption enhancement with the surface-active agent is carried out with a view to further understand the absorption enhancement mechanism of surface-active agent. It is concluded that the Maragoni instability is mainly responsible for enhanced mixing, thereby enhancing absorption.


Sign in / Sign up

Export Citation Format

Share Document