GELENEKSEL KANATÇIKLI BLOK VE KISMİ ALÜMİNYUM VE BAKIR METAL KÖPÜK YERLEŞTİRİLMİŞ ISI ALICILARIN ISIL PERFORMANSLARININ KARŞILAŞTIRILMASI

Öz

Bu araştırmada, 4,8,16 gözenek/cm oranında 0,93 gözenekliliğe sahip alüminyum ve 0,90 gözenekliliğe sahip bir bakır metal köpükler kullanılarak özel bir geometriye sahip ısı alıcı tasarlanmış ve test edilmiştir. Deneyler sırasında, metal köpük entegre edilerek üretilmiş ısı alıcıların ısıl dirençleri ve basınç kayıpları, farklı ısı akıları (10.67, 15.75, 21.33 ve 31.50 kW / m2) ve iki ayrı ön hava hızı (4 ve 6 m/s) uygulanarak test edilmiştir. Isı alıcıların ısıl performanslarındaki farklılıklar, özel olarak ürettirilen ısıtıcıların kullanılarak gözlenmiştir. Test sonuçları, köpük ısı alıcılarının basınç düşüşünün kanat bloğundan yaklaşık dört kat daha fazla olduğunu göstermektedir; köpük ısı emicilerinin ortalama konveksiyon ısı transfer katsayıları ısıtıcı yüklerine bağlı değildir ve köpük bölümlerinin taban plakası sıcaklıkları, köpüksüz bölümlerden 1 ila 1.5 derece daha düşüktür. Bu ısı alıcı tasarımı, elektrikli cihazların bileşenlerinin istenen konumlarında geleneksel tip bir kanatçıklı bloktan daha düşük sıcaklıklar sağlamıştır.

Anahtar Kelimeler

• Bakır Köpük
• Alüminyum Köpük
• Lehimleme Yöntemi
• Zorlanmış Konveksiyon
• İletim
• Isıl Yönetim

A COMPARISON OF THE THERMAL PERFORMANCE OF A CONVENTIONAL FIN BLOCK AND PARTIALLY COPPER AND ALUMINUM FOAM EMBEDDED HEAT SINKS

Öz

In this research, the metal foams with 4,8,16 pores/cm, an aluminium foam which has 0.93 porosity and a copper foam which has 0.90 porosity that are integrated into a heat sink with a special geometry were designed and tested. During the process of the experiments, the thermal resistances and the pressure losses of the metal foam integrated heat sinks were tested by applying different heat fluxes (10.67, 15.75, 21.33 and 31.50 kW/m2) and two distinct frontal air velocities (4 and 6 m/s) to the specimens. The differences in the thermal performances of the heat sinks were observed by enforcing the custom-made manufactured heaters. The test results demonstrate that the pressure drop of the foam heat sinks is approximately four times more than the fin block; the average convection heat transfer coefficients of foam heat sinks are not dependent to the heater loads and the base plate temperatures of the foam sections were 1 to 1.5 degree lower than the foamless sections. This heat sink design provides lower temperatures on the desired locations of the electrical components than a conventional type fin block.

Anahtar Kelimeler

• Copper Foam
• aluminum foam
• soldering method
• forced convection
• conduction
• thermal management

Kaynakça

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