Compliant Fluidic Control Structures: Concept and synthesis approach. (May 2019)

• Record Type: Journal Article
• Authors: Kumar, Prabhat; Fanzio, Paola; Sasso, Luigi; Langelaar, Matthijs
• Is Part Of: Computers & structures. Volume 216(2019)
• Page Start: 26
• Page End: 39
• Publication Date: 2019-05
• Subjects: Compliant structures -- Microfluidic devices -- Topology optimization -- PDMS -- Nonlinear finite element analysis; Structural engineering -- Data processing -- Periodicals; Electronic data processing -- Structures, Theory of -- Periodicals; 624.171
• DOI: 10.1016/j.compstruc.2019.02.004
• Languages: English
• ISSNs: 0045-7949

Abstract

Highlights: Concept and synthesis approach for CFCSs which can find application in biomedicine/drug delivery. Use of thickness design variables with large deformation under plane-stress conditions. An objective using hydraulic diameter is minimized for the desired modes of the functional pores. Use of Arruda-Boyce material definition to model PDMS in the TO setting. Comparison of the performances of the fabricated CFCFs with their respective numerical models. Abstract: The concept and synthesis approach for planar Compliant Fluidic Control Structures (CFCSs), monolithic flexible continua with embedded functional pores, is presented in this manuscript. Such structures are envisioned to find application in biomedicine as tunable microfluidic devices for drug/nutrient delivery. The functional pores enlarge and/or contract upon deformation of the compliant structure in response to external stimuli, facilitating the regulated control of fluid/nutrient/drug transport. A thickness design variable based topology optimization problem is formulated to generate effective designs of these structures. An objective based on hydraulic diameter(s) is conceptualized, and it is extremized using a gradient based optimizer. Both geometrical and material nonlinearities are considered. The nonlinear behaviour of employed hyperelastic material is modeled via the Arruda-Boyce constitutive material model. Large-displacement finite element analysis is performed using the updated Lagrangian formulation in plane-stress setting. The proposed synthesis approach is applied to various CFCSs for a variety of fluidic control functionalities. The optimized designs of various CFCSs with single and/or multiple functional pores are fabricated via a Polydimethylsiloxane (PDMS) soft lithography process, using a high precision 3D printed mold and their performances are compared with the numerical predictions.