Fluid–Structure Interaction in the Flexible Porous Stratification Manifold

Abstract

A model of the flexible porous manifold that captures the interaction between the flow field and the deformation of the manifold is developed and applied to understand how the fabric manifold works for conditions expected in solar water heaters. Contrary to the widely held hypothesis that the change of cross-sectional area induced by the fluid–structure interaction is beneficial, the numerical results demonstrate the change of cross-sectional area has no significant impact on the effectiveness of the manifold. In comparison to a rigid porous manifold, the performance of the flexible manifold is slightly worse because the collapse of the manifold encourages entrainment. The dimensionless permeability plays a crucial role in determining the performance and can be selected to limit entrainment and release fluid near the vertical level of neutral buoyancy.