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Hygric and Thermal Simulation

In special cases it is necessary to perform a three dimensional thermal simulation. HTflux is purely two-dimensional as it was optimized for fast and efficient thermal bridge calculation. Although based on the same physics, three dimensional simulations involve a disproportionate effort compared to 2d-simulations. Especially the creation of the model as well as the finite element meshing are time consuming and require a certain level of skill. The time to perform a 3d-simulation is usually increased by a factor of 10 or more, compared to a 2d-simulation having the same number of details. Therefore we recommend that if you do need a three dimensional simulation you should contact us. With our experience combined with the use of modern academic simulation software we are able to perform 3d-thermal simulation efficiently and accurately. We can therefore offer you this service at a very competitive price level.

Just like 2d simulations performed with HTflux, 3d finite element thermal simulations offer you a lot of insights regarding potential optimizations and enable you to calculate design values, such as:

  • point transmittance value (χ-value, “chi”-value)
  • minimum surface temperatures
  • distribution of temperature
  • distribution of heat flux

Below find an exemplary 3d simulation of a steel roof anchor mounted on a flat concrete roof, penetrating the insulation layer:

flat-roof-steel-anchor-post-finite elements-thermal simulation

3d simulation model – steel roof anchor on a flat concrete roof with thermal insulation

3d-FEM-Thermal simulation-Thermal bridge-mesh

Optimized 3d finite element mesh

3d-Thermal-simulation-roof anchor post-isosurfaces

Temperature distribution (iso-surfaces) in the area of the point thermal bridge


semi-transparent 3d view of the heat-flux


building-science-3d-simulation-Temperatures on external side

FEM-Simulation temperature view external side (thermal bridging)

FEM-3d-point-transmittance-internal surface temperatures

FEM-Simulation temperature view internal side (thermal bridging)

Another simple example of a comparative study recently done:

Thermal bridge, 3d-fem-simulation, building science, daniel rüdisser

point thermal bridging, 3d-heat flux, simulation