Continua of the Differential Type
Let us consider now nonideal continua. Practically all real bodies are nonideal media, and they can be considered as ideal ones in a certain approximation. According to the general theory of constitutive equations stated in Sect. 4.4.2, a continuum is nonideal if its operator constitutive equations (4.158) include the dissipation function w∗being nonzero.