پديد آورنده :
فضل اللهي، فريد
عنوان :
بررسي تجربي تاثير ميدان الكتريكي قوي برانتقال حرارت درون محفظه ها ي پره دار
مقطع تحصيلي :
كارشناسي ارشد
گرايش تحصيلي :
تبديل انرژي
محل تحصيل :
اصفهان:دانشگاه صنعتي اصفهان،دانشكده مكانيك
صفحه شمار :
سيزده،128ص.: مصور﴿رنگي﴾،جدول،نمودار
يادداشت :
ص.ع.به فارسي و انگليسي
استاد راهنما :
علي اكبر عالم رجبي
استاد مشاور :
محمدرضا سليم پور
توصيفگر ها :
الكتروهيدروديناميك , محفظه هاي پره دار روزنه دار
تاريخ نمايه سازي :
25/2/89
استاد داور :
احمد صابونچي،ارجمند مهرباني
چكيده فارسي :
به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي
چكيده انگليسي :
Experimental Investigation of the Effect of High Voltage Electric Field on Heat Transfer within Finned Enclosures Farid Fazlollahi f fazlollahi@me iut ac ir Date of Submission 15 3 2010 Department of Mechanical Engineering Isfahan University of Technology Isfahan 84156 83111 IranDegree M Sc Language FarsiSupervisor Ali Akbar Alemrajabi rajabi@cc iut ac irAbstractHeat transfer enhancement leads to Performance Improvement of heat exchangers and a considerabledecrease in their size In general enhancement techniques can be divided into two groups namely active andpassive techniques The active techniques require external forces e g electric field acoustic or surfacevibration The passive techniques require special surface geometries such as rough surface extendedsurface etc or fluid additives The electrohydrodynamics EHD augmentation of heat transfer refers tocombination of electric field and fluid field in a dielectric fluid domain Almost all previous investigations onEHD enhanced heat transfer are focused on flat surfaces and unfinned enclosures or channels and there isvery few literatures related to EHD effect on the open cavity or finned enclosures It would be an advantageif one could couple passive and active techniques which is the subject of the present study In this work enhancement of heat transfer in partially open finned enclosure has been investigated experimentally Fivefaces of the enclosure were thermally and electrically insulted and one face was a finned copper plate Effectof number of fins i e 1 3 and 7 was investigated An aperture was located in a face opposite to the copperplate whose height is 7 5cm The dimensions of the enclosure are 15cm 20cm and it has 15cm high Thefins are made of commercial pure copper with thickness of 3mm and their lengths are one quarter of theenclosure widths Apart from the copper plate other walls of the enclosure are made of the Plexiglas flatplate with a thickness of almost 3 2mm The Plexiglas plates were coated with layers of the asbestos andnylon to decrease the heat loss Atmospheric air can convect naturally within the enclosure The wireelectrodes used for applying electric field were installed near fins also at three positions at top bottom and infront of fins The other considered parameters include the applied current applied voltage and different typesof corona discharge It was concluded that heat transfer is enhanced while the applied current and voltageincreased Moreover higher location of the aperture can lead to more enhancement of heat transfer by EHD The best location for electrode was in front of the fins Increase of distance between the plate and wireelectrodes when the applied current is constant leads in increase in heat transfer The positive corona is moreeffective on enhancing heat transfer when the number of electrodes is increased from one to seven Keywords Electrohydrodynamics Heat transfer enhancement Finned enclosures Natural convection
استاد راهنما :
علي اكبر عالم رجبي
استاد مشاور :
محمدرضا سليم پور
استاد داور :
احمد صابونچي،ارجمند مهرباني
