Thermo-mechanical coupling

Glacier-permafrost coupling creates a distinctive hydraulic regime, dominated by transient processes, which must be understood for long term safety assessments. In principle, the problem should be solved by a thermo-mechanically coupled model of the whole ice-water-rock system, driven by an external climate function. As an interim step, we use two separate models, one for... 

A thermo-mechanically coupled, transient ice sheet model (Boulton and Payne, 1994), coupled with the Earth model of Lambeck et al., (1998) has been driven by the climate function over a prescribed topography of North America with a 10 km resolution. The model computes the temperature at the base of the ice sheet and the rate of basal melting in time and space. This is used to compute the spacing between channels that are required to exist at the ice/bed interface to discharge meltwater that cannot be discharged by groundwater flow (Boulton et al., 2(X)1), and the head distribution at the ice/bed interface. 

As a general rale, visco-plastic material behavior is specified for FEM simulation of chip removal. Thermo-mechanically coupled calculations are used. For describing material behavior, the use of the Johnson-Cook equation (Eq. 4) is preferred. Another semiempiiical model presented by Zerilli and Armstrong considers micro-mechanical effects in relation to the thermal activation behavior of face-centered (fee) and body-centered cubic (bcc) structures of the workpiece material. Other constitutive material laws are formulated by Oxley, Clifton Hensel-Spittel, and El-Magd, respectively, whereas the stress s is determined by different linear or exponential procedures within the equation terms. 

Ames, N. M., Srivastava, V., Chester, S. A., and Anand, L. (2009) A thermo-mechanically coupled theory for large deformations of amorphous polymers. Part II applications, Int. J. Plasticity, 25, 1495-1539. 

Arruda, E. M., Boyce, M. C., and Jayachandran, R. (1995) Effects of strain rate, temperature and thermo mechanical coupling on the finite strain deformation of glassy polymers, Mech. Mater., 19, 193-212. 

Chen, X., Yan, L, Wang, Z., and Liu, D. (2011) Out-of-phase thermo-mechanical coupling behavior of proton exchange membranes. /. Power Sources, 196, 2644-2649. 

Toda, A., Tomita, C., Hikosaka, M., Hibino, Y., Miyaji, H., Nonomura, C., Suzuki, T., and Ishihara, H. (2002) Thermo-mechanical coupling and self-excited oscillation in the neck propagation of PET films. Polymer,... 

Gawin, D., Pesavento, F. and Schrefler, B. A. (2002) Simulation of damage - permeability coupling in hygro-thermo-mechanical analysis of concrete at high temperature, Comm. Num. Meth. Engrg. 18, 113-119... 

Ulm, F.-J. and Coussy, O. (1995) Modeling of thermo-chemo-mechanical couplings of concrete at early ages. J. Eng. Mech. ASCE 121(7), 785-794... 

All these processes are the product of a system driven by the Earth s climate and characterised by strong thermo-hydro-mechanical coupling, in which both chemical processes and transient phenomena are important. 

This paper presents a numerical simulation of the swellin shrinking processes using the numerical model RF-TH/M - a fully coupled thermo-hydraulic model with mechanical coupling - which has been developed for the purpose of modelling non-isothermal multiphase flow in swelling porous media. In this paper details of the mathematical and numerical multiphase-multicomponental formulation for bentonite, as well as code implementation are described. As an example a test case is investigated. 

This model is implemented in the novel object-oriented simulator RockFlow-TH/M - a fully coupled thermo-hydraulic model with mechanical coupling, which can be used to simulate non-isothermal moisture transport processes and the corresponding swelling effects. 

Stephansson et al., O. 1995. Thermo -Hydro -Mechanical Coupling in Rock Mechanics. 

Fredriksson, A., Staub, I., Janson, T. 2003. Aspo Pillar Stability Experiment. Design of heaters and preliminary results from coupled 2D thermo-mechanical modelling. SKB, IPR-03-03. Swedish Nuclear Fuel and Waste Management Company, Stockholm. 

Abstract motif is a three-dimensional finite-element code developed to simulate groundwater flow, heat transfer and solute transport in deformable fractured porous media. The code has been subjected to an extensive verification and updating programme since the onset of its development. In this paper, additional verification and validation works with an emphasis on thermo-hydro-mechanical processes are presented. The verification results are based on cases designed to verify thermo-hydro-mechanical coupling terms, and isothermal and non-isothermal consolidations. A number of validation case studies have been conducted on the code. Example results are repotted in this paper. 

ON THE CONSTITUTIVE MODELLING OF THERMO-HYDRO-MECHANICAL COUPLING IN ELASTIC MEDIA WITH DOUBLE POROSITY... 

Collin, F. Li, X.L. Radu, J.P. Charlier, R. 2002a. Thermo-hydro-mechanical couplings in clay barriers. Engineering Geology (64) pp. 179-193. 

Stereo-complex films were reported by Masutani et al7 % combining bifunctional PLLA and PDLA pre-polymers, multi-stereo-block copolymers having different block lengths and sequences are obtained. The resultant copolymers are readily fabricated into transparent films by hot-pressing. The films present excellent thermal stability and thermo-mechanical properties because of the easy formation of stereo-complex crystals. This synthetic method based on tbe dual terminal couplings allows obtaining stereo-block copolymers of PLLA and PDLA showing excellent thermo-mechanical properties and melt processability. 

Thus, a better understanding of the container/content interactions is essential. This can be achieved by coupling thermo mechanical and physicochemical studies of the interaction between polymer packaging and product. The feedback of such studies will allow constructive and sustainable industrial development to protect the packaging from all constraints and preserve the packed product quality and integrity. 

S. Koric S, et al., Explicit coupled Thermo-mechanical Finite Element Model of Steel Solidification", IntemationalJoumal for Numerical Methods in Engineering, 78 (1) (2009), 1-31. 

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