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

Yıl 2010, Sayı: 023, 49 - 58, 15.12.2010

Bayram Alakuş

Öz

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.

Anahtar Kelimeler

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

Öz

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.

Anahtar Kelimeler

İzotermal olmayan gözenekli ortam akışı, matematiksel modelleme, REV

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