Hydrodynamic Force and Heat/Mass Transfer From Particles, Bubbles, and Drops—The Freeman Scholar Lecture

2003 ◽  
Vol 125 (2) ◽  
pp. 209-238 ◽  
Author(s):  
Efstathios E. Michaelides

Recent advances on the analytical form of the hydrodynamic force and heat/mass transfer from a particle, bubble, or drop are examined critically. Also some of the recent computational studies, which help strengthen or clarify our knowledge of the complex velocity and temperature fields associated with the momentum and heat/mass transfer processes are also mentioned in a succinct way. Whenever possible, the processes of energy/mass exchange and of momentum exchange from spheres and spheroids are examined simultaneously and any common results and possible analogies between these processes are pointed out. This approach results in a better comprehension of the transport processes, which are very similar in nature, as well as in the better understanding of the theoretical expressions that are currently used to model these processes. Of the various terms that appear in the transient equations, emphasis is given to the history terms, which are lesser known and more difficult to calculate. The origin, form, and method of computation of the history terms are pointed out as well as the effects of various parameters on them. Among the other topics examined here are the differences in the governing and derived equations resulting by finite Reynolds and Peclet numbers; the origin, theoretical validity and accuracy of the semi-empirical expressions; the effects of finite internal viscosity and conductivity of the sphere; the effects of small departures from the spherical shape; the effects of the finite concentration; and the transverse, or lift, components of the force on the sphere.

2006 ◽  
Vol 289 (2) ◽  
pp. 652-658 ◽  
Author(s):  
V.N. Popov ◽  
Yu.S. Tsivinskaya ◽  
T.B. Bekker ◽  
K.A. Kokh ◽  
A.E. Kokh

Author(s):  
Satish G. Kandlikar ◽  
Mark E. Steinke

Heat and mass transfer processes become highly efficient as the channel hydraulic diameter is reduced in size. Biological systems, such as human body, rely on the extremely efficient transport processes occurring at microscale in the functioning of its vital organs. In this paper, the transfer processes in lungs and kidneys will be reviewed. Although the flow in the microchannels present in these organs is laminar, it yields very high mass transfer coefficients due to the coupling of small channel diameters. Furthermore, the molecular transport mechanisms occurring across the membranes at nanoscales through diffusion controlled processes also become extremely important. Understanding these transport processes will enable us to develop more efficient artificial organs and processes that closely mimic the performance of the natural systems. These ideas can be extended to other microscale system designs in different technologies, such as IC cooling and MEMS micro fuel cells.


10.12737/4522 ◽  
2014 ◽  
Vol 4 (2) ◽  
pp. 166-177
Author(s):  
Соколовский ◽  
Yaroslav Sokolovskiy ◽  
Крошный ◽  
Igor Kroshnyy ◽  
Прусак ◽  
...  

In the paper there is described solving a current scientific problem of mathematical modeling of heat-mass transfer processes and elastic-viscous-plastic deformation taking into account the mechanics and sorption creep in hygroscopic capillary-porous materials with variable anisotropic heat and mechanics characteristics what is of importance for the rational choice and substantiation of energy conservative technologies of timber drying under the conditions of necessary qualitative production providing.


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