👉 The Sec Fluid, also known as the Smallest Particle Viscosity or S-PV, is a measure of the internal friction within a fluid at very small scales, typically in the nanometer range. It quantifies how easily a fluid flows when subjected to shear stress at these minuscule dimensions, reflecting the molecular interactions and the fluid's resistance to deformation. Unlike macroscopic viscosity, which is measured at larger scales, Sec Fluid captures the complex, non-Newtonian behavior of fluids in confined spaces, such as at interfaces or within microfluidic devices. This parameter is crucial for understanding and designing systems where fluid behavior at the nanoscale significantly impacts performance, such as in lab-on-a-chip technologies and biological microenvironments.
