Main >> Applications >> Sample problems

# ISO 10211:2007 Thermal bridges in building construction. Test case A.3 validation

ISO 10211:2007, thermal bridges in building construction

QuickField validation of the test case A.3 presented in ISO 10211:2007 Thermal bridges in building construction.

Problem Type
3D problem of heat transfer.

Geometry

Given
Thermal conductivity of materials:
AAC λ1 = 0.7 W/K-m.
Insulation λ2 = 0.04 W/K-m.
Brick λ3 = 1.0 W/K-m.
Concrete slab λ4 = 2.5 W/K-m.
Plaster λ5 = 1 W/K-m.

The floor slab penetrates the wall near the corner and forms the cold bridge. Determine the flux and the thermal coupling coefficients.

Solution
Air contact surface thermal resistance Rs is caused by the convection. The convection coefficient value is reciprocal to the surface resistance value:
α = 1 / Rs [W/(K·m²)].

Results
Temperature distribution in media (click to see 3D view):

 Temperature in the corners: Heat flux: QuickField Reference %% First floor 11.12°C 11.11°C <0.1 K Second floor 11.37°C 11.32°C <0.1 K 59.4 W 59.98 W 1%

Thermal coupling coefficients (reference values are in the brackets).

 External First floor Second floor External (1.000) (0.000) (0.000) First floor 0.375 (0.378) 0.401 (0.399) 0.223 (0.223) Second floor 0.329 (0.331) 0.216 (0.214) 0.455 (0.455)

To comply with the ISO 10211:2007 the difference between calculated and reference heat flux should be less than 2% (0.1°K - for temperature). This simulation accuracy complies with the requirements of ISO 10211:2007.