NSF Travel Award for student SeonHong Na.

PhD student of the poromechanics group, SeonHong Na, has been awarded travel award to attend EMI Stanford. He will present his work on stability and dispersion analysis of wave propagation in thermo-sensitive porous media. Congratulations SeonHong! 

The abstract of the presentation is listed below. 

Thermo-hydro-mechanical coupling effects on wave propagation and strain localization in a softening fully saturated porous medium

SeonHong Na, WaiChing Sun, Department of Civil Engineering and Engineering Mechanics, Fu Foundation School of Engineering and Applied Science, Columbia University, New York

We investigate analytically the thermo-hydro-mechanical (THM) coupling effects on the length scale of fully saturated porous media under non-isothermal condition. By extending the previous works on stability and dispersion analyses on isothermal porous media, we analyze the stability of the system of equation subjected to harmonic perturbations and derive the expression of length scale and phase  velocity of the non-isothermal porous media as a function of mechanical, hydraulic and thermal material properties. We prove that the new expression of length scale is consistent with the classical results under limited conditions such as undrained, drained, adiabatic and isothermal conditions. Both one- and three-dimensional wave propagation simulations are conducted using a stabilized mixed THM model to compare the results from stability and dispersion analyses. Our analytical results and  numerical experiment both indicate that while permeability and thermal conductivity may affect the  thickness of plastic zones, introducing multi-physical coupling effect alone does not guarantee the cure of mesh dependency when strain localization occurs. 

Keywords: thermos-hydro-mechanical coupling effect, porous media, wave propagation, stability,  dispersion, internal length scale.