Performance analysis of pin fins with temperature dependent thermal parameters using the variation of parameters method

Abstract

The performance of pin fins transferring heat by convection and radiation and having variable thermal conductivity, variable emissivity and variable heat transfer coefficient was investigated in the present paper. Nondimensionalizing the fin equation, the problem parameters which affect the fin performance were obtained. Dimensionless nonlinear fin equation was solved with the variation of parameters method, which is quite new in the solution of nonlinear heat transfer problems. The solution of variation of parameters method was compared with known analytical solutions and some numerical solution. The comparisons showed that the solutions are seen to be perfectly compatible. The effects of problem parameters were investigated on the heat transfer rate and fin efficiency and results were presented graphically.

Isıl parametreleri sıcaklıkla değişen iğne kanatların, parametrelerin değişimi yöntemi ile performans analizi

Öz

Bu çalışmada, taşınım ve ışınımla ısı kaybeden ve ısı iletim katsayısı, ısı taşınım katsayısı ve yayma oranı sıcaklıkla değişen iğne kanatların ısıl performansları araştırılmıştır. Kanat denklemi boyutsuzlaştırılarak, kanat performansını etkileyen boyutsuz problem parametreleri elde edilmiştir. Doğrusal olmayan boyutsuz kanat denklemi, daha çok homojen olmayan doğrusal diferansiyel denklemlerin çözümünde kullanılan ve doğrusal olmayan denklemlerin çözümü için de kullanılabileceği yakın zamanlarda kanıtlanan parametrelerin değişimi yöntemi ile çözülmüştür. Parametrelerin değişimi yöntemi çözümü, bilinen analitik çözümlerle ve bazı sayısal çözümlerle karşılaştırılmış ve sonuçların mükemmel bir uyum içinde olduğu görülmüştür. Isı transfer hızı ve kanat verimine boyutsuz problem parametrelerinin etkileri araştırılmış ve sonuçlar grafiksel olarak sunulmuştur.

Anahtar Kelimeler

• İğne kanatlar, Değişken ısı iletim katsayısı, Değişken ısı taşınım katsayısı, Değişken yayma oranı, Parametrelerin değişimi yöntemi

Kaynakça

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