Abstract




 
   

IJE TRANSACTIONS C: Aspects Vol. 28, No. 3 (March 2015) 460-466   

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  STUDY OF DEGRADATION OF DRY COOLING TOWER PERFORMANCE UNDER WIND CONDITIONS AND METHOD FOR TOWER EFFICIENCY ENHANCEMENT (RESEARCH NOTE)
 
M. A. Ardekani, F. Farhani, M. Mazidi and M. A. Ranjbar
 
( Received: November 09, 2013 – Accepted: December 18, 2014 )
 
 

Abstract    Wind affects adversely the cooling tower thermal performance. A field investigation was carried out to study the thermal performance of Heller cooling towers under wind conditions, involving measurement of wind velocity and its direction around the cooling tower, and obtaining water flow rates and temperatures at the cooling tower inlet and outlet. Results show that air suction at the tower top prevents flow separation at tower periphery. Additionally, due to better airflow distribution over the front cooling sectors, perpendicular to wind direction, the thermal efficiency is improved compared to the sectors on the tower periphery, parallel to wind direction, resulting in about 20% more heat transfer. Moreover, the thermal performance of the front sectors improves with increase in the wind velocity, while it decreases with increase in the wind velocity for the periphery sectors and those at the back of the tower.

 

Keywords    Cross wind velocity, Cooling tower, Field measurements, Thermal performance, Wind direction

 

چکیده    وزش باد تاثير نامطلوبي بر عملکرد حرارتي برجهاي خنک کن هلر دارد. در اين بررسي يک مطالعه ميداني بر روي عملکرد حرارتي برجهاي خنک کن خشک هلر تحت شرايط مختلف وزش باد انجام گرفته است و سرعت وزش باد در اطراف برج خنک کن و دبي و دماي آب ورودي و خروجي از برج اندازه گيري شده است. نتايج بدست آمده نشان مي دهد که مکش هوا توسط برج مانع از وقوع پديده جدايش در اطراف برج در قسمت قرارگرفتن رادياتورها مي گردد. علاوه بر اين نتايج بيانگر اين مطلب است که راندمان رادياتورهاي قرار گرفته در سمت رو به باد، با افزايش سرعت باد افزايشي حدود 20% را داشته ولي در عوض راندمان رادياتورهاي قرار گرفته در کناره هاي برج که مماس بر جهت وزش باد هستند و همچنين رادياتورهاي پشت به باد که در قسمت پشت برج قرار گرفته اند کاهش راندمان دارند

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