The Optimization of Koch Fractal Micromixer with Snowflakes Structure
Devi Fitria Nurvadila1, Roer Eka Pawinanto2, Budi Mulyanti2, Ahmad Aminuddin1, Chandra Wulandari1,3, Lilik Hasanah1*

1Departement of Physics Education, Universitas Pendidikan Indonesia, Bandung 40154, Jawa Barat, Indonesia
2Departement of Electrical Engineering Education, Universitas Pendidikan Indonesia, Bandung 40154, Jawa Barat, Indonesia
3Engineering Physics, Institut Teknologi Bandung, Bandung 40132, Jawa Barat, Indonesia

Abstract

The development of micromixer device has grown rapidly due to significance in miniaturization of complex biological and chemical processing system. High mixing efficiency and low Reynolds (Re) number is a key performance expected from a micromixer device in microfluidic system. The performance could be enhanced by the complex structure of Koch fractal arranged at the top and bottom of the T-micromixer. In this work, the mixing efficiency of different level on Koch snowflake fractal are compared and the thickness of Koch fractal are optimized. COMSOL Multiphysics has been used to simulate the mixing process in microchannel and obtain the value of mixing efficiency for each geometries with thickness variations 0.01-0.19 mm. The influences of Re number on mixing efficiency was investigated in the range 0.05 - 100. The result has been indicated the higher level of fractal obtained better mixing efficiency. The homogenous mixing in the meander structure has showed as well as high mixing efficiency that reaches 0.99. The thickness linearly influences mixing efficiency, where the optimum performance obtained by 0.19 mm of thickness and Re 0.1. Therefore, it can be stated that the reported meander structure has a high performance and applicable to support the development of Lab on Chip for various application.

Keywords: microfluidic mixer, Koch snowflakes fractal, mixing efficiency, Reynolds number

Topic: Physics