Refractive-index-matched hydrogel materials for modeling flow-structure interactions

Abstract

In imaging-based studies of flow around solid objects, it is useful to have materials that are refractive-index-matched to the surrounding fluid. However, materials currently in use are usually rigid and matched to liquids that are either expensive or highly viscous. This does not allow for measurements at high Reynolds number, nor accurate modeling of flexible structures. This work explores the use of two hydrogels (agarose and polyacrylamide) as refractive-index-matched models in water. These hydrogels are inexpensive, can be cast into desired shapes, and have flexibility that can be tuned to match biological materials. The use of water as the fluid phase allows this method to be implemented immediately in many experimental facilities and permits investigation of high Reynolds number phenomena. We explain fabrication methods and present a summary of the physical and optical properties of both gels, and then show measurements demonstrating the use of hydrogel models in quantitative imaging.

References in corpus (2)

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Cited by in corpus (6)

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• Experimental investigation of turbulent suspensions of spherical particles in a square duct
• Rotational diffusion of particles in turbulence
• Buoyant finite-size particles in turbulent duct flow
• On the micro PIV accuracy and reliability utilizing suspension particles of large, non-Gaussian particle image