What is a constitutive formulation in continuum mechanics Co

What is a constitutive formulation in continuum mechanics? Compare and contrast this to a descriptive formulation. Why is it important to develop constitutive models?

Solution

Continuum mechanics is a branch of mechanics that deals with the analysis of the kinematics and the mechanical behavior of materials modeled as a continuous mass rather than as discrete particles.

constitutive equation or constitutive relation is a relation between two physical quantities (especially kinetic quantities as related to kinematic quantities) that is specific to a material or substance, and approximates the response of that material to external stimuli, usually as applied fields or forces. They are combined with other equations governing physical laws to solve physical problems; for example in fluid mechanics the flow of a fluid in a pipe, in solid state physics the response of a crystal to an electric field, or in structural analysis, the connection between applied stresses or forces to strains or deformations.

Descriptive formulation is helpful for calculations and to arrive at statistical tools such as median, averages, and frequencies.

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