The sound of viscosity

摘要

Though viscosity is the degree to which a fluid resists flow, it is more specifically a measure of a fluid's molecular friction. It can be a useful property to quantify because it gives an indirect measurement of a liquid's consistency in both molecular weight and molecular-weight distribution. Viscosity can give other insights into materials and properties that can be val-uable in manufacturing processes. Trouble is, almost all methods for measuring viscosity were developed originally for laboratory analysis. They were never intended for making measurements quickly. They certainly are not amenable to the sort of real-time environment that characterizes modern-day manufacturing or processing. So it has not been practical to use viscosity measurements for, say, adjusting liquid properties on the fly, or for tweaking recipes as processing environments change.