Thermo-mechanics model

Lhuillier, D. Thermo-mechanical modelling of nematic polymers. In Continuum Thermodynamics Maugin, G.A., Drouot, R., Sidoroff, F.S., Eds. Kluwer Dordrecht, 2000 237-246. 

Previous to the general simulation of the experiment, a comparison between the results of a Thermo-mechanical modelling of different geometries is presented. This is panicularly important, as boundary conditions play a fundamental role in the thermal problem. Small changes on the geometry may lead to very different predictions on heater temperature. Finally, the prediction of temperature and degree of saturation in a mid plane for hole nr 1 is presented, and results are compared with the field data available. A list of the parameters and physical laws involved in the simulations has been included as well, in order to illustrate the basic data used in the analyses. 

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. 

THERMO-MECHANICAL MODELING OF A SUBSURFACE INTERIM NUCLEAR WASTE STORAGE BEHAVIOR IN WORKING CONDITIONS... 

In 1992, McManus and Springer [5, 6] presented a thermomechanical model that considered the interaction between mechanically induced stresses and pressures created by the decomposition of gases within the pyrolysis front. Again, temperature-dependent mechanical properties were determined at several specified temperature points as stepped functions. The issue of degradation of material properties at elevated temperatures was considered in Dao and Asaro s [7] thermo-mechanical model in 1999. The degradation curves used in the model were, once again, obtained by curve fitting of limited experimental data. 

Spina, R. Tricarico, L. BasUe, G. Sibillano, T. (2007). Thermo-mechanical modeling of laser welding of AA5083 sheets. J. Mater. Process. TechnoL, Vol. 191, 215-219. 

Thermo-mechanical modeling and simulation should account for the compression of the porous media and the membrane in terms of thickness reduction, deflection into the gas channel (LFSI), and local variations of the material parameters (e.g., reduced porous media porosity and permeability). Another topic is the description of the... 

Thermo-mechanical models are hybrids of heat transfer and finite element models of residual strength. Through-thickness temperature profiles and resin mass-loss data from the thermal components of these models have been used respectively to prediet residual modulus and increase in pressure due to accumulated volatiles within the burning composite material. It remains for such models to a) adequately represent mixed modes of mechanical failure b) accurately model ply layer delamination, and c) correctly model the directionality of thermally-induced strains as a function of ply orientation. 

McManus, (1992) Thermo-mechanical model for carbon-phenohe/ carbon-carbon composites Added modeling of ablation of the polymer surface. Most comprehensive model at that time. [50-51]... 

However, when a material is a structural composite of resin and continnons reinforcement such as carbon fiber or woven E-glass, the task of representation by finite element methods is considerably more complicated. Regardless of this difficulty, there are a considerable number of workers who specialize in these types of thermo-mechanical models, [64-88], who have published modeling woik specifically in this area for many years. The key concept used in such models is the idea of temperature-dependent material modulus, and how this can be calculated in tandem with through-thickness solid-temperature models generated in the Henderson tradition. 

Other related phenomena which have received attention within some thermo-mechanical models are those of thermal expansion and ply delamination within polymer composites during thermal degradation leading to mechanical failure. For example, two equations to describe expansion effects have been proposed by Florio et al. [87], (equations 14.19 and 14.20). 

Overall, despite the doubtless advances made by authors in the development of representative thermo-mechanical models, there still remain some substantial challenges before a fully predictive and integrated thermo-mechanical solution to the problem of composite failure during combustion can be finalized. Some of the remaining requirements are as follows ... 

Thus it can be seen that while there are a range of substantial challenges which must be addressed in order to advance thermo-mechanical modeling, both the diversity of ideas generated and the rate of development in this area are perhaps sufficient to indicate that a fully validated, hybrid thermo-mechanical model of composite thermal response, decomposition, combustion and mechanical failure may soon be achieved. 

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