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ISO 10077-2:2012 Test case D.2 - Aluminium clad wood frame section and insulation panel

QuickField simulation example

QuickField simulation of the test case "D.2. Aluminium clad wood frame section and insulation panel" presented in ISO 10077-2:2012*

Problem Type
Plane-parallel problem of heat transfer.

ISO 10077-2:2012 Test case D.2 - Aluminium clad wood frame section and insulation panel Calculate two-dimensional thermal conductance T = +20°C, Rs = 0.13 m²K/W T = 0°C, Rs = 0.04 m²K/W Aluminium Air Soft wood EPDM Insulation panel 110 mm Zero thermal flux

Frame width b = 110 mm

Thermal conductivity of EPDM, λ1 = 0.25 W/K-m.
Thermal conductivity of insulation panel, λ2 = 0.035 W/K-m.
Thermal conductivity of aluminium, λ3 = 160 W/K-m.
Thermal conductivity of soft wood, λ4 = 0.13 W/K-m.

Calculate two-dimensional thermal conductance L2D in accordance with ISO 10077-2:2012*.
(Reference thermal conductance L2D = 0.263 W/(m*K) )

Air contact surface thermal resistance Rs is caused by convention mechanism of heat transfer (contrary to conductivity mechanism in case of two solid bodies in contact).
The convection coefficient value is reciprocal to the surface resistance value:
α20 = 1/0.13 W/(K·m²),
α0 = 1/0.04 W/(K·m²).

Thermal conductivities of air gaps are adjusted to include the convection and radiation heat transfers in real situation, and correlated with the actual temperatures on the gap contours according to the recommendation of ISO 10077-2:2012. Equivalent air gap conductivity calculations are automated in the accompanying Excel spreadsheet.

Heat flux distribution in frame section profile:
EN ISO 10077:2012 D2 heat flux

Two-dimensional thermal conductance L2D = Heat flux per meter depth / Temperature difference = 5.33 / 20 = 0.266 W/(m*K).
Difference between the calculated and reference values is less than 3%. This simulation accuracy complies with the requirements of ISO 10077-2:2012.

* ISO 10077-2:2012 Thermal performance of windows, doors and shutters -- Calculation of thermal transmittance -- Part 2: Numerical method for frames.