Site Loader
Rock Street, San Francisco

Pool heat transfer is an incredible and challenging area for carrying out research activities tofulfill the requirements of various industrial/ research sectors such as thermal and nuclearpower plants, metallurgy, petroleum industry, chemical plants, food processing andrefrigeration. This heat transfer phenomena occur in different stages like pure convection orboiling heat transfer depends on power source temperature in the pool. Pure convection isgenerally used in power plants such as shell tube heat exchangers, heat transfer throughsubmerged pipelines, steam pipes and cooler pipes as a conventional method for extractingheat without having problem of failure of active component like pump and any extra costburden. Thermo convective flows induced by vibrations in reduced gravity field studied topredict the behaviour of operated fluid use in spacecraft by Shevtsova et al. 2008, 2010. Inthe field of metallurgy, Heat transfer of single or two phase fluid system in rectangular cavityunder vibration has great deal of attention vibration play a key role in metal casting process(Road and Fadda 1997), (Y.K. Oh et al. 2002), Chang (2007).In the pool heating, the nucleate boiling has the largest heat transfer coefficient whichimposed better heat transfer than other stages. Therefore, it is frequently used in the nuclearengineering like in the reactor core to extract heat from fuel bundles, Pool heat exchangersassociated with passive residual heat removal systems, isolation condenser systems, andpassive containment cooling systems, as described by Cummins et al. (2003), and in theaerospace engineering as described by Himeno et al. 2008, 2010, and 2011 for strengthenthe heat transfer.During the process of nucleate boiling, heat removes from heated surface by means of thetiny bubbles generated in micro cavities and grow up. Since bubbles are accountable fordegree of dissipation of heat by boiling heat transfer, it is significant to understand themechanism behind the formation, growth and detachment from the boiling surface. Thedetachment of the bubble from the surface is influenced by the various forces acting ongrowing bubble. Out of various forces acting on the bubble during its growth, the major forceresponsible for attachment of bubble to the heated surface is surface tension whereas thebuoyancy force is accountable for detachment of the bubble. During initial growth stage ofbubble the surface tension force dominants the buoyancy force. However, with increase insize of the bubble, buoyancy force gradually supersedes the surface tension force. When themagnitude of buoyancy force becomes much higher than the surface tension force, the bubbledetach from the heated surface. So, the formation, growth and detachment of the bubble andthe rate of heat transfer thereof require the knowledge of bubble dynamics parameters. Thesebubble dynamics parameters are nucleation site density, bubble departure diameter, bubblewaiting period, bubble growth period and bubble departure frequency.

Post Author: admin

x

Hi!
I'm Anna!

Would you like to get a custom essay? How about receiving a customized one?

Check it out