Experimental Investigation of Heat Transfer Characteristics over Rectangular Fin Surfaces by Taguchi Method

Abstract

In this study, the effects of flow velocity, fin height, and the number of fins on heat transfer over heated rectangular fin surfaces were experimentally investigated using the Taguchi method. Experiments were conducted in a low-speed wind tunnel with surfaces having consecutive 7, 8 and 9 fins with heights of 12, 18 and 24 mm, and for flow velocities of 3, 10, and 15 m/s. Free stream and wall temperatures were measured with thermocouples, and the Stanton number was considered as the performance parameter. An L8 orthogonal array was chosen as the experimental design, and the results were analyzed in terms of signal-to-noise (S/N) ratio and the analysis of variance (ANOVA) method to determine the optimal conditions. Heat transfer over fin surfaces increased with fin height, fin numbers, and flow velocity. While the most effective parameters in increasing heat transfer were flow velocity and fin height, respectively, the least effective parameter was determined as the number of fins. The optimal result was obtained with 9 fins of 24 mm height on the surface at a flow velocity of 15 m/s.

Keywords

• Rectangular fin
• Taguchi method
• Stanton number
• Heat transfer
• Wind tunnel

Dikdörtgen Kanatlı Yüzeyler Üzerindeki Isı Transfer Karakteristiklerinin Taguchi Yöntemiyle Deneysel Olarak İncelenmesi

Öz

Bu çalışmada ısıtılmış dikdörtgen kanatlı yüzeyler üzerinden akışta akış hızı, kanat yüksekliği ve kanat sayısının ısı transferi üzerindeki etkileri Taguchi yöntemiyle deneysel olarak incelenmiştir. Deneyler 12, 18 ve 24 mm kanat yüksekliğinde ardışık 7, 8 ve 9 adet kanada sahip yüzeyler üzerinden 3, 10 ve 15 m/s akış hızları için düşük hızlı bir rüzgâr tünelinde yapılmıştır. Serbest akış ve duvar sıcaklıkları termal çiftler ile ölçülmüş ve performans parametresi olarak Stanton sayısı dikkate alınmıştır. Deneysel plan olarak L9 ortogonal dizisi seçilmiş ve sonuçlar sinyal-gürültü (S/N) oranı ve ANOVA yöntemi kullanılarak en uygun koşullar açısından analiz edilmiştir. Kanatlı yüzeyler üzerinde akışta ısı transferi kanat yüksekliği, kanat sayıları ve akış hızıyla artmıştır. Isı transferini arttırmak için en etkili parametre sırasıyla akış hızı ve kanat yüksekliği iken, kanat sayısı en az etkili parametre olarak belirlenmiştir. En iyi sonuç 9 adet 24 mm kanat yüksekliğine sahip yüzey üzerinde 15 m/s akış hızında elde edilmiştir.

Anahtar Kelimeler

• Dikdörtgen kanat
• Taguchi yöntemi
• Stanton sayısı
• Isı transferi
• Rüzgar tüneli

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