Previously we modeled the theoretical benefits of using microfluidic channels that utilize a “Cathedral Chamber” design, in which the ceiling is supported by an array of periodic posts, compared to an array of parallel microfluidic channels. We developed a semi-automated technique that combines a rule-base defect placement system with a Monte Carlo method for modeling the fluid dynamics and blockage formation based on the likelihood of blockages forming in areas of high particle traffic and low flow rate. Earlier results indicate that Cathedral Chambers, that are supported by an array of 10 by 11 periodic posts with the same size as the spacing have six times higher lifetime expectancy compared to an array of 10 parallel channels, likely due to the provision of multiple paths during localized blockage formation in the Cathedral Chamber. In this paper, we have expanded our investigations by considering the defect tolerance sensitivity to scale by altering parameters such as the number and size of the posts and overall size of the chamber. For one set of simulations, we used the same number of posts in the chamber and the same starting position for the first 10 blockages as in our previous work. However, we shrank the size of the posts to 66% of their former size so that the new channels (flow pathways) are twice the size of the modified posts. In addition, we have also performed initial simulations based on wider microfluidic channels supported by an array of 20 by 11 periodic posts in order to explore their microfluidic behavior and lifetime.

Date Published: 24 March 2015
PDF: 10 pages
Proc. SPIE 9320, Microfluidics, BioMEMS, and Medical Microsystems XIII, 93200B (24 March 2015); doi: 10.1117/12.2080870

Published in SPIE Proceedings Vol. 9320:
Microfluidics, BioMEMS, and Medical Microsystems XIII
Bonnie L. Gray; Holger Becker, Editor(s)