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

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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