Computational Fluid Structure interaction of novel mSLA 3D printed lung-on-a-chip microdevice

3D printing has been employed for microfluidic device fabrication as an alternative to soft lithography due to its superior scalability and architectural complexity. Here, we developed a 3D computational fluid dynamics (CFD) fluid–structure interaction (FSI) model of a novel 3D‑printed microfluidic system used to model the alveolar-capillary barrier. The device features a nonlinear elastic extracellular matrix membrane, which exhibits radial stretching in response to the actuation of integrated polymer films. We utilized an experimentally validated COMSOL model to simulate strain across the membrane, local shear‑rate profiles, and membrane deflection to study effects on cell behavior, as well as a parametric study of polymer stiffness, its geometrical characteristics, and flow rate to quantify membrane deflection and resulting strain and shear. We simulated strain up to 12% and observed that at >6% strain and >8 µL/min flow rate, shear effects dominate. Additionally, we found that altering the stiffness of the actuating polymer membranes by 0.5 GPa impacts membrane deflection by up to 35%. This computational toolkit enables optimization of dynamic MPS, which may result in more physiologically relevant structures helpful for use in drug discovery and disease modeling.