Modelling of Diffusion in Random Packings of Core-Shell Particles

Yıl 2017, Cilt: 45 Sayı: 2, 269 - 275, 01.06.2017

Emre Hatipoğlu Harun Koku

Öz

Core-Shell particles are commonly used materials in chromatography. In this study, a mathematical model that mimics diffusion around Core-Shell particles was developed. A random-walk based algorithm was implemented to simulate diffusion and a Core-Shell particle geometry was computationally formed, based on simple geometric constructs and relations. Diffusion simulations were carried out on a randomly packed geometry formed from these particles. The behavior of time-dependent diffusivity data obtained from the model was found to be consistent with prior literature data from nuclear magnetic resonance experiments where transient diffusivity of a self-diffusing substance was measured in porous media.

Anahtar Kelimeler

Core-Shell, Diffusion, Random-Walk, Geometry

Çekirdek-Kabuk Parçacıklarının Raslantısal Paketlemelerinde Difüzyonun Modellenmesi

Öz

Ç ekirdek-Kabuk tipi parçacıklar kromatografide sıklıkla kullanılan malzemelerdir. Bu çalışmada, ÇekirdekKabuk parçacıklarının etrafında gerçekleşen difüzyonu taklit etmeye yönelik bir matematik modeli geliştirilmiştir. Difüzyonun simulasyonu için rastgele-yürüyüş temelli bir algoritma oluşturulmuş ve basit geometrik yapılar ve bağıntılardan oluşan bir Çekirdek-Kabuk geometrisi hesaplanmıştır. Bu parçacıklardan oluşan rastgele-istiflenmiş bir yapı üzerinde difüzyon simülasyonları gerçekleştirilmiştir. Model sonuçlarından elde edilen zamana bağlı difüzyon katsayısının davranışı, nükleer manyetik rezonans deneyleri vasıtasıyla gözenekli ortamlarda bir maddenin zamana bağlı öz-difüzyon katsayısının ölçüldüğü daha önceki bir çalışmanın sonuçlarıyla uyumludur

Anahtar Kelimeler

Çekirdek-Kabuk, Difüzyon, Rastgele-Yürüyüş, Geometri.

Kaynakça

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