AKIŞ YÖNLENDİRİCİ PLAKANIN ÇIKINTILI ISI KAYNAKLARINDAN KARIŞIK KONVEKSİYONLA ISI TRANSERİNE ETKİSİ

Bu çalışmada, akış yönlendirici plaka kullanımının alt ve üst yüzeylerinde çıkıntılı ısı kaynakları bulunan yatay bir kanal içerisindeki karışık konveksiyonla laminar ısı transferine etkisi sayısal ve deneysel olarak incelenmiştir. Soğutucu akışkan olarak hava kullanılmış olup ısı kaynakları duvarları yalıtılmış olan dikdörtgen kanal içerisine 8x4’lük diziler halinde yerleştirilmiştir. Deneysel çalışma iki farklı Reynolds sayısı (Re) için yapılmıştır. Deneysel çalışma sonuçları ile uyumlu bir sayısal model oluşturulmuş ve sayısal çalışma 0°, 30°, 60° plaka açıları için farklı Re ve Grashof (Gr) sayılarında gerçekleştirilmiştir. Analizler akış yönlendirici plaka kullanımının yalnızca alt yüzeyde ilk dört ısıtıcı sırası için, üst yüzeyde ise ilk ve son ısıtıcı sıraları için ısı transferini artırdığını göstermiştir. Deneysel ve sayısal çalışma sırasında elde edilen bulgular sıra ortalama Nusselt sayısı (Nusıra ort.), ısıtıcı sıcaklıkları, hız vektörleri ve sıcaklık kontörlerini gösteren grafikler halinde ayrıntılı olarak sunulmuştur.

EFFECTS OF FLOW ROUTING PLATE ON MIXED CONVECTION HEAT TRANSFER FROM PROTRUDED HEAT SOURCES

In this study, the effect of the flow routing plates on the laminar mixed convection heat transfer in ahorizontal channel that has protruded heat sources at the bottom and top surfaces were investigated numerically andexperimentally. The air was used as the cooling fluid, and protruded heat sources were equipped as 4x8 rows into therectangle channel that has insulated walls. The experimental study was applied for two different Reynolds (Re)numbers. A numerical model complying with the experimental results was created, and numerical investigations wereperformed in different Reynolds and modified Grashof (Gr*) numbers for the 0°, 30°, 60° values of the plate angles(α). The analyses showed that using flow routing plate only increases the heat transfer from the first four heater rowson the bottom surface, and the first and the last heater rows on the top surface. The findings obtained during theexperimental and numerical studies were presented in detail as graphics showing the row averaged Nusselt number(Nurow ave.), the heater temperatures, velocity vectors, and temperature contours.

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