Warning: mktime(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone. in /home/ale10001/public_html/libraries/joomla/utilities/date.php on line 117

Warning: strftime(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone. in /home/ale10001/public_html/libraries/joomla/utilities/date.php on line 250

انتقال حرارت توأم با تقطير بخار آب در مبدلهاي لوله – پره اي

Research Area: Technology management Year: 1997
Type of Publication: Article
Authors: Shokouhmand, Hossein; Ebrahim, Nader Ale
Journal: نشریه دانشکده فنی Volume: 1
Number: 59 Pages: 69-80
Abstract:
مبدلهاي حرارتي انبساط مستقيم سيال عامل لوله اي با پرده هاي مسطح بطور وسيعي در سيستمهاي تهويه مطبوع كاربرد دارد . يكي از موارد استفاده اين مبدلها سرمايش و رطوبت گيري همزمان مي باشد. در صورتيكه هواي عبوري از روي كويل مرطوب بوده و دماي كويل زير نقطه شبنم هواي ورودي باشد. بر روي پرده هاي كويل تقطير صورت مي گيرد. در اين پژوهش يك مبدل دو رديفه با آرايش لوله هاي مثلثي،جهت بررسي پديده انتقال حرارت و جرم در نظر گرفته شده است. با يك تحليل دو بعدي روي يك سلول واحد از اين مبدل ، معادلات حاكم بدست آمده است. به دليل بررسي همزمان هدايت در پره و جابجايي روي سطح آن معادلات بهم وابسته و مكانيزم انتقال حرارت بصورت توأمان مي باشد. اين معادلات به روش اختلاف محدود حل گرديده و توزيع دما و راندمان پره تحت شرايط سطح تر و خشك با تغيير گام و جنس پره،دما و رطوبت هواي ورودي وعدد رينولدز جريان بدست آمده است. نتايج نشان ميدهند كه با افزايش هدايت حرارتي پره مقاومت حرارتي كاهش يافته وتغييرات دماي پره در جهت شعاعي از مركز به خارج كاهش مي يابد و راندمان پره بيشتر مي شود. يعني جنس پره سهم مهمي در راندمان پره دارد . همچنين در يك جنس معين پره،با افزايش گام پره ويا بالا رفتن دما ويا رطوبت هواي ورودي راندمان كاهش مي يابد . بعلاوه راندمان پره با سطح مرطوب،پايين تر از راندمان يك پره خشك مي باشد. اثر انتقال جرم با در نظر گرفتن ضريب تقطير موضعي،C لحاظ شده است. چکیده (انگلیسی): Direct Expansion plate finned tube coils (DX) are extensively used in air conditioning systems. If the air flowing over the coil is humid and the coil temperature is below the dew point, condensation will occur on the fins. In this paper a two-row unit (DX) in which the tubes are arranged triangular, has been selected for analysis of sene sible and latent heats.By applying a tow-dimensinal analysis on an individual cell of the coil, the governing equations have been derived. These equations have been solved numerically using a finite difference method. The temperature distribution and fin efficiency variation for both wet and dry surface conditions, versus the fin pitch, fin material, temperature and humidity of the inlet air flow and Reynolds number, have been determined.
[Bibtex]

Citation Counting

Upcoming Events

Latest Images

Download Files 


Warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone. in /home/ale10001/public_html/libraries/joomla/utilities/date.php on line 198
UMISCA-How to write a review paper By Nader Ale Ebrahim
15-02-2013-UM-UMISCA-The Effective Use of Research Tools and Resources
UM-21-01-2013- The Effective Use of Research Tools Box and Resources
UPM - 16-01-2013, Research Tools II - By: Nader Ale Ebrahim
UKM- 06-01-2013- Practical Guide to Write a PhD Thesis and publish papers based on the thesis By: Nader Ale Ebrahim
UPM - 09-12-2012, Research Tools I  - By: Nader Ale Ebrahim

Latest Publication

Latest Contents 


Warning: strtotime(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone. in /home/ale10001/public_html/libraries/joomla/utilities/date.php on line 56

Warning: date(): It is not safe to rely on the system's timezone settings. You are *required* to use the date.timezone setting or the date_default_timezone_set() function. In case you used any of those methods and you are still getting this warning, you most likely misspelled the timezone identifier. We selected the timezone 'UTC' for now, but please set date.timezone to select your timezone. in /home/ale10001/public_html/libraries/joomla/utilities/date.php on line 198

Warning: Creating default object from empty value in /home/ale10001/public_html/modules/mod_latestnews/helper.php on line 109

Warning: Creating default object from empty value in /home/ale10001/public_html/modules/mod_latestnews/helper.php on line 109

Warning: Creating default object from empty value in /home/ale10001/public_html/modules/mod_latestnews/helper.php on line 109

Warning: Creating default object from empty value in /home/ale10001/public_html/modules/mod_latestnews/helper.php on line 109

Warning: Creating default object from empty value in /home/ale10001/public_html/modules/mod_latestnews/helper.php on line 109

Warning: Creating default object from empty value in /home/ale10001/public_html/modules/mod_latestnews/helper.php on line 109

Warning: Creating default object from empty value in /home/ale10001/public_html/modules/mod_latestnews/helper.php on line 109