Eğimli Dikdörtgen Bir Kanalda Köpük Isı Alıcılardan Doğal Taşınımın Deneysel Olarak İncelenmesi

Bu çalışmada, eğimli dikdörtgen bir kanalda, 5x1diziliminde alüminyumdan yapılmış köpük ısı alıcılarından doğal taşınımla ısı transferi incelenmiştir. Alüminyum köpük ısı alıcılar Al-6101 alaşımında yapılmıştır. Kanalın alt duvarına monte edilen bütün ısı alıcılar ayrık formda yerleştirilmiş ve sabit ısı akısına maruz bırakılmıştır. Deneylerde farklı gözenek yoğunluğuna sahip (10, 20 ve 40 PPI) metal köpük malzemeler kullanılmıştır. Soğutma akışkanı olarak hava (Pr =0.7) kullanılmıştır. Deneyler Rayleigh sayısının 2.03 x107 ila 1.33 x108 arasındaki değerleri ve kanal eğim açısı 0° ila 90° arasında değişen değerleri için yapılmıştır. Ayrıca, alüminyum köpük ısı alıcılardan elde edilen ısı transferi sonuçları düz yüzeyler (köpük olmayan) için elde edilen sonuçlarla karşılaştırılmıştır. Elde edilen sonuçlar, hem kanal eğim açısının ve hem de köpük ısı alıcıların kullanılmasının, ısı transfer sonuçları üzerinde önemli etkileri olduğunu göstermiştir.

Experimental Investigation of Free Convection from Foam Heat Sinks in an Inclined Rectangular Channel

Inthis present study, free convection from an in-line 5x1 array of aluminum foamheat sinks which were placed on the bottom wall of the inclined rectangularchannel was investigated. Aluminum foam heat sinks were made of Al-6101 alloy.All heat sinks mounted on a bottom wall of the channel was discrete form andexposed to uniform heat flux. Aluminum foam materials with three different poredensities (10, 20 and 40 PPI) were used in experiments. Air was used as coolantfluid (Pr =0.7). The experiments were made for Rayleigh Number range from 2.03x107 to 1.33 x108 and the channel inclination angles werevaried from 0° to 90°. Moreover, the heat transfer results fromthe aluminum foam heat sinks were also compared to the results obtained forfoam-free (without foam) surfaces. The results showed that both the channelinclination angle and the usage of foam heat sinks are significant influenceson heat transfer results.

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