NON-ISOTHERMAL FLOW MODELS WITH MASS DIFFUSION FOR A STATIONARY POROUS MEDIA BY EMPLOYING REPRESENTATIVE ELEMENTARY VOLUME

Abstract

Nowadays, in many industrial applications, porous materials play an important role in the design and development processes. For instance, in alloy solidification, between the solid and the fluid phases there is a region called mushy zone which contains both fluid and solid. Its structure is very complicated but can be handled as an anisotropic porous medium with directional variation in permeability. Other industrial applications such as flow over heat exchanger matrices, flow through turbo-machines, primary and secondary oil recoveries etc. can very well be approximated as porous media. Finally, it seems appropriate to mention that cooling of electronic micro systems is becoming more and more important as much of our modern day equipment contains more and more electronic circuits. In order to increase their performance and life, it is essential to have proper cooling arrangement. A reliable flow and heat transfer prediction in these arrangements is always difficult due to the complexity of flow structure. However, a porous medium approximation to such problems can be efficient. The generalized procedure described in this study is a good approximation for these structures.

Keywords

• Non-isothermal Porous media flow,Mathematical modelling,Representative Elementary Volume (REV)

İZOTERMAL OLMAYAN VE KÜTLESEL DİFÜZYONUN MEVCUT OLDUĞU DURGUN BİR GÖZENEKLİ ORTAM İÇERİSİNDEKİ AKIŞKAN AKIŞININ TEMSİLİ BİR TEMEL HACİM KULLANILARAK MODELLENMESİ

Abstract

Günümüz teknolojisinde, birçok endüstriyel uygulamada gözenekli materyaller dizayn ve geliştirmede önemli bir rol oynar. Örneğin, katılaşma problemindeki katılaşma esnasında oluşan katı ve akışkan bölgeleri bu ortama bir örnektir. Bu problem çok zor bir problem olmakla birlikte, gözenekli ortam akış modeli kullanılarak çözülebilir. Birkaç diğer uygulama örnekleri ise ısı değiştirgeçleri, termik-turbu makinalardaki akışlar, petrol çıkarılması ve proseslere tabi tutulması  sayılabilir. Son bir örnek olarak, performans ve ömürlerinin arttırılması için, elektronik mikro sistemlerin soğutulması bu akış modeli kullanılarak yapılabilir. Bu çalışmada tanımlanan prosedüre ve model, bu türlü problemlerin çözümünde iyi  ve güvenilir sonuçlar verir.

Keywords

• İzotermal olmayan gözenekli ortam akışı,matematiksel modelleme,REV

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