WOOD RESEARCH Volume 67, Number 2, 2022
LINDA MAKOVICKA OSVALDOVA, PAULINA MAGDOLENOVA, Frank Markert, SAMUEL L. ZELINKA, LOUISE FREDERIKKE ENOKSEN, and MALTHE KLINT

Modelling a clt specimen protected with gypsum exposed to parametric fire curve heat flux

This paper models bench-scale experiments using computational fluid dynamics (CFD). The experiments measured the temperature profiles of fire-protected cross laminated timber (CLT) specimens exposed to parametric fire curve. The bench-scale experiment specimen is 250 x 250 mm and consists of a CLT panel 100 mm with three layers of gypsum plasterboard 15.5 mm as thermal and fire insulation The specimens were exposed to a heat flux generated by a heat-transfer rate inducing system (H-TRIS) device. Two numerical models were created in order to copy the experiment conditions, one by using basic modelling techniques and one using advanced method. Comparing the layer temperature values of the experiment and basic model, a great difference was found. The difference between experimental and model temperatures increases the closer the analysed layer is to the heat source. The results show a good agreement between the model and the experiments, especially for the advanced numerical model.

WOOD RESEARCH Volume 66, Number 1, 2021
Juraj Jancík, Linda Makovická Osvaldová, and Frank Markert

Thermogravimetric analysis, differential scanning calorimetry and time-to-ignition of wood materials treated with water glass flame retardants

The paper investigates efficiency of silicate flame retardants on wooden fibres (used for production of medium-density fibreboards) and spruce boards. A simultaneous thermal analysis and cone calorimetry were used for the assessment. Specimens were treated with three different types of silicate water glass: sodium silicate, potassium silicate and modified silicate. Along with these, one sample of untreated fibres was tested in order to provide a baseline sample. As a result of the simultaneous thermal analysis, the ability of the treatments to increase the residual amount of biological char in samples during pyrolysis and ability of the flame retardant to be retained in these wood fibres was used to assess the efficiency of each flame retardant on the wood fibres.