Flowresistant

Flowresistant is a term used to describe the property of a material, surface, or component that impedes the passage of fluids. In practice, flowresistant materials hinder fluid flow more than a reference configuration. The degree of flowresistance depends on geometry, porosity, pore size distribution, thickness, and tortuosity, as well as surface chemistry and roughness, and on fluid properties such as viscosity and density.

Quantification of flowresistance is typically expressed as a pressure drop per unit flow rate, ΔP/Q, or as a material constant in Darcy-like relations. In porous media, ΔP = μ (L/K) Q. In channels and pipes, geometry and boundary conditions determine the effective resistance; higher flowresistance yields a larger pressure drop for the same flow.

Applications of flowresistant materials and surfaces include limiting leakage or penetration of liquids and gases, such as in filtration membranes, waterproof textiles, barrier coatings, and seals. In microfluidics and instrumentation, controlled flowresistance enables regulated fluid distribution or prevention of backflow.

Notes: The term is not uniformly standardized; it is often described with hyphenated forms like flow-resistant, or described via related concepts such as permeability, leak-rate, or hydraulic resistance. In biological contexts, flow resistance describes the opposition to blood or airway flow, but that usage denotes physiological resistance rather than material design.