Numerical investigation of design of a passive micromixer compound shape on split and recombination concept

Öz

Microchannels are a key component of these devices, and micromixers are the heart of these channels. The related study aims to produce micromixers with high efficiency with a simple shape. This work presents the design and numerical performance analysis of the flow using Computational Fluid Dynamics (CFD). This work is based on the SAR (Split and Recombination) concept with a zigzag shape. The mixing was investigated over a wide range of Re numbers (1-100). Four factors with three levels were optimized by the Taguchi method to achieve the optimal shape: angle, several periods, the ratio between width to diameter, width, and depth. The index of mixing is evaluated and focused on the variance of the fraction of the mass in the mixture. As a result, the index of mixing is enhanced with varied Reynolds numbers. The mixer with a 70°, 4-period (w/d=0.125) and (w/t=1) design was the optimal choice.

Anahtar Kelimeler

• Computational Fluid Dynamics
• Mixing Index
• Passive Micromixer
• Spilt and recombination
• Optimization

Pasif mikro karıştırıcı için zikzak şeklinde bölme ve rekombinasyon kavramını içeren tasarımın sayısal olarak incelenmesi

Öz

Mikro kanallar cihazların bir parçasıdır ve mikro karıştırıcılar kanalların kalbidir denilebilir. İlgili çalışma, akışın tasarımını ve performans analizini Hesaplamalı Akışkanlar Dinamiği (HAD) ile sayısal olarak açıklamaktadır. Bu çalışma, zikzak şekilli SAR konseptine dayanmaktadır. Karıştırma, geniş bir Re sayısı aralığında (1-100) incelenmiştir. En uygun şekli elde etmek için üç seviyeli dört faktör Taguchi yöntemi ile optimize edilmiştir; açı, periyot, genişlik ile çap arasındaki oran arasındaki ilişki için de genişlik ve derinlik incelenmiştir. Karıştırma indeksi, karışımdaki kütle kesrinin varyansına odaklanarak değerlendirilmektedir. Sonuç olarak, karıştırma indeksi değişen Reynolds sayılarıyla arttığı görülmüştür. Karıştırıcıdaki en iyi tasarım 70o, 4-periyotlu, (w/d=0.125) ve (w/t=1) koşullarında elde edilmiştir.

Anahtar Kelimeler

• Hesaplamalı akışkanlar dinamiği (HAD)
• Karıştırma İndeksi
• Pasif Mikromikser
• Bölünme ve Rekombinasyon
• Optimizasyon

Kaynakça

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