2010

Solar air heater with an inclined, flow crossing absorber

Eğik bir cam toplayıcı kanalından geçmekte olan hava, dikdörtgen kesitli , cam kanal içine, tekrar boylamasına çapraz yerleştirilen, siyaha boyanmış, delikli, bakır bir levha yardımı ile güneş enerjisi tarafından ısıtıldı. Kanalın boyutları; 18,5 cm en, 9,5 cm yükseklik ve 2,5 m uzunluk olup kanaldaki absorplama yüzeyi % 3 delikli idi. Yatışkın halde eğik abzorberli koşulda h2 (ort.) 23 W/(m2K) ve h3 (ort.) 150 W/(mK) değerleri tabana paralel yerleştirilen levha durumunda elde edilen h2 (ort.) 34 W/(m2K) ve h3 (ort.) 15 W/(m2K) değerleri ile kıyaslandığında deliklerin çevresinde yüksek türbülans ve bunun sonucunda da yüksek ısı aktarım katsayıları elde edildiği anlaşıldı. Absorberin eğik olduğu koşulda; teorik tüm ısı aktarım katsayısı $U_{lt}$ 7-14 W/(m2 K),verimliliği $eta$ c% 44 ile yüksek bir h3 elde edildi.

Akıma çapraz abzorberli, eğik, güneş enerjili hava ısıtıcısı

Air was solarly heated in an inclined , rectangular glass channel equipped with a black painted, perforated, inclined copper plate which was longitudinally crossing the flowing air in the collector channel. The dimensions of the channel were 18.5 cm width, 9.5 cm height and 2.5 m length with a 3 % perforation area of absorber plate fitting in the channel. Strong turbulence was achieved around the holes and virtually higher efficient heat transfer coefficients were obtained at the steady-state conditions as h2 (ave.) 23 W/(m2K) and h3 (ave.) 150 W/(m2K) when compared with h2 (ave.) 34 W/(m2K) and h3 (ave.) 15 W/(m2K) of parallel absorber at the bottom of the collector. in the case of inclined absorber plate a high h3 was obtained; with a theoretical overall heat transfer coefficient of $U_{lt}$: 7-14 W/(m2K) and (ave.) 44 % effıciency($eta$ c).

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