Abstract




 
   

IJE TRANSACTIONS C: Aspects Vol. 28, No. 6 (June 2015) 940-948    Article in Press

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  A NUMERICAL INVESTIGATION ON AERODYNAMIC COEFFICIENTS OF SOLAR TROUGHS CONSIDERING TERRAIN EFFECTS AND VORTEX SHEDDING
 
Z. Baniamerian, R. Mehdipour and F. Kargar
 
( Received: January 09, 2015 – Accepted: May 02, 2015 )
 
 

Abstract    Recently, increase in the cost of fossil fuels and taking into consideration the environmental effects of exploiting them, caused many researchers and governments to find some ways to make use of renewable energies more cost-effectively. Solar energy is a category of renewable energies which could be harvested via several technologies. One of the most practical methods is using parabolic troughs. In solar power plants, many parabolic troughs are set in parallel rows in order to concentrate the solar power onto a tube absorber. In designing and manufacturing parabolic troughs and their structures, it is essential to take into account the wind force. Any negligence in considering the wind force could be concluded in losing the accuracy and efficiency. In this article, the aerodynamic coefficients of parabolic solar troughs have been investigated using CFD methods. The variations of aerodynamic coefficients considering terrain effects, the angle of collectors and the gap between mirrors have been studied. Also, it will be demonstrated that in order to properly align trough collector in solar farms, it is essential to study the vortices shed created at the behind of parabolic troughs and its effects on collectors’ structures in the result of wind interaction. At the end and as an illustration, the drag and lift coefficients of collectors have been calculated in Yazd power plant.

 

Keywords    solar trough collector, aerodynamic coefficient, numerical analysis, vortex shedding

 

چکیده    افزايش قيمت سوختها استفاده از انرژي نو را در جايگاه ويژه اي قرار داده است. انرژي خورشيدي يكي از موضوعات مورد توجه براي توليد انرژي مي باشد. در طراحي كلكتورهاي خورشيدي مهمترين نيرو نيروي باد بوده است و بايد در طراحي كلكتور مقاومت در برابر اين نيرو مورد حساب قرار گيرد. در اين مقاله نكات و نحوه محاسبه ضرايب آيروديناميك بر كلكتور خورشيدي به كمك روش CFD نشان داده مي شود. نشان داده مي شود كه مدلسازي گردابه هاي پشت كلكتور بسيار مهم بوده و ميزان ضريب درگ، ليف و فركانس نيروي باد بر كلكتور خورشيدي نيروگاه يزد ايران محاسبه مي شود. تغييرات ضرايب در زاويه كلكتور و اثر زمين و شيارهاي بين آينه ها بررسي ميگردد.

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