Nano-pores in a thermo-elastic continuum with strain gradient effects

The thermo-mechanical balance equations for a porous material with big irregular pores are derived from the general ones for a medium with ellipsoidal microstructure by imposing the kinematical constraint of microstretch bounded to the macrodeformation: in this case the microstructure disappears apparently (it becomes latent) and the response of the material involves higher gradients of the displacement without incurring known constitutive inconsistencies.