GOVERNING EQUATIONS FOR ISOTHERMAL FLOW THROUGH WOVEN FIBER MATS BY EMPLOYING LOCAL VOLUME AVERAGING TECHNIQUE

Year 2011, Issue: 024, 91 - 106, 15.04.2011

Bayram Alakuş

Abstract

Accurate
mathematical modeling of resin flow in liquid composite molding (LCM) processes
is important for effective simulations of the mold-filling process. Recent
experiments indicate that the physics of resin flow in woven fiber mats is very
different from the flow in random fiber mats. In this study, the mathematically
rigorous volume averaging method is adapted to derive the averaged form of mass
and momentum balance equations for unsaturated flow in LCM. The two phases used
in the volume averaging method are the dense bundle of fibers called tows, and
the surrounding gap present in the woven fiber mats. Averaging the mass balance
equation yields a macroscopic equation of continuity which is similar to the
conventional continuity equation for a single-phase flow. Similar averaging of
the momentum balance equation is accomplished for the dual-scale porous medium. 

Keywords

Porous media flow, Mathematical modelling, Resin transfer moulding (RTM), Local volume averaging

FİBERLİ GÖZENEKLİ BİR ORTAMDAKİ İZOTERMAL BİR AKIŞKANIN YEREL HACİMSEL ORTALAMA METODU KULLANILARAK HAREKET DENKLEMLERİNİN ELDE EDİLMESİ

Abstract

Sıvı kompozit kalıp işlemi 
sırasındaki resin akışının doğru bir matematiksel modelinin
oluşturulması, simülasyon ve kalıp doldurma işlemi için çok önemlidir. Bu
çalışmada, yerel hacimsel ortalama metodu detaylı olarak kullanılmak sureti ile
akış alanına ait  kütle ve momentum
denklemleri elde edildi. Oluşan matematiksel model  akışkan resine ait ortalama hız bileşenleri
ile basıncı verir. Benzer ortalama teknikleri ile, çift skalalı gözenekli
ortama ait  momentum balans deklemleri
elde edilebilir.

Keywords

Gözenekli ortam akışı, matematiksel modelleme, RTM

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