experiments

This paper describes the latest developments in the simulation of a thermal probe apparatus, building on earlier work as reported by de Wilde et al. (2007). The work focuses on researching the role of the probe to sample conductance H. Results obtained with the existing model are proven to be inconclusive, and necessitate the change to flexible general engineering finite element software. 

The use of a thermal probe allows a range of in-situ conditions to be taken into account that impact upon the properties of building materials (λ, α) as encountered in reality. In this study, the transient thermal simulation of a model representing a line source in an infinite material sample has been used to guide the development of an experimental thermal probe apparatus. Simulation produced a series of datasets that have been used to test the data analysis routines used with the experimental probe.

The evolution of the temperature profile in a warm room driven by a natural ventilation flow which develops when the room is connected to a cold exterior by two openings at different vertical heights is explored. With the openings at the top and base of the room, we find the classical displacement ventilation regime provides a leading order description of the flow. With openings at the centre and top of the room, the ventilation is hybrid, with the lower part of the room being well-mixed, and the upper part being stratified by an upward displacement ventilation flow.