From theory to modelization… The thermophysical properties identification of composite material requires the use of specific computer softwares. After a long study of the phenomenon of thermal transfers in orthotropic heterogeneous materials, I have decided to develop SimTTheC in order to smartly modelize their thermal behaviors.
Main features of SimTTheC
SimTTheC mesh and results Imposed temperature gradient on the two sides of a strongly heterogeneous triaxial composite.
4Non-stationary 3D simulations of heat transfers in heterogeneous and orthotropic solids. 4Choice of discretization method : finite differences or finite volumes. 4Various kind of composites. 4Differents boundaries conditions allowed. 4Wide possibilities of visualization. 4The speed and the stability of the ADI algorithm. SimTTheC has been largely used by ONERA, particularly on problems of atmospheric re-entry of a space ship demonstrator. The SimTTheC software SimTTheC is written in Fortran and is using a graphical interface developed under Visual Basic. SimTTheC is Windows friendly. The visualization of the results can be done with Excel, Matlab or Tecplot.
Microscopic modelization of composite materials SimTTheC c an take into account the microscopic structure of a composite and differents geometries are allowed.
From modelization to experimental measurement… A new kind of testing bench associated with SimTTheC was conceived and validated. It measures simultaneously the three orthotropic conductivities of a composite and its heat capacity in less than four hours. The sample is heated by a laser and the heat flow is identified at the beginning of the experiment. Infra-red thermography associated with SimTTheC authorizes a great flexibility and a simplification of the measurements.
This job in the laboratories of ONERA represents : 4Three years of management of a research project. From the development of the numerical simulation software to the building of the testing bench. 4Three years of training in aerothermic, infra-red thermography and data processing. 4Three years with a technical team in an international research center near to industrial applications.
Identification of the laser heat flow An inverse method using Discrete Cosine Transforms can measure the space distribution of the heat flow delivered by the laser which heats the composite.
Heating of an honeycomb composite plate The internal structure of the plate is revealed by infra-red thermography as well as the orthotropic diffusion of heat.
The testing bench On the left, the laser heats the composite which is captive of a vacuum chamber. On the right, the infrared camera and its PC record the temperature of its back during the experiment.
Vincent Plana --- (33) 06-89-06-07-19 ---
[email protected] --- http://simtthec.free.fr
