Measurements of specific heat capacity of common building materials at elevated temperatures: a comparison of DSC and HDA

Abstract

The objective of this study is to investigate how the specific heat capacity (cp) value of a material changes with respect to temperature and heating rate of that material. In-depth knowledge in the variation of cp will provide a better knowledge of the thermo-physical properties of these materials and will increase the capabilities and fidelity of computational fluid dynamics (CFD)-based fire modelling. The models and simulations are reliant on input data gained through experimentation and this allows for the present study to provide such input data and trends, which are useful in understanding how fires respond in different situations. The value of cp in relation to the rate of temperature change has been measured using differential scanning calorimetry (DSC) and hot disk analysis (HDA). This study encapsulates the determination of cp values, trends and equations for poly(methyl methacrylate), pinewood, pinewood char, and two fabrics: cotton and wool. The cp values were found to increase with the sample temperature and for the two fabrics; they vary with the change in heating rate. The derived equations show that cp values from DSC and HDA are comparable. To include these relationships in CFD-based fire models, a set of suggestions have been made.