LAUSR

Abstract Indoor airflow can be complex due to large regions with no dominant flow direction and low velocities. An airborne material released from a surface indoors would be expected to result in a high degree of variability in concentration. It is currently not known how the spatially and temporally resolved concentration field from this type of source could be exploited for the detection of contaminants or vapour from concealed materials. Previous experimental and numerical work has provided information on flow and passive scalar transport in indoor environments but little on how different detection/search strategies could be employed in these environments. This work used large-eddy simulation to extensively study the turbulence fluctuations and the instantaneous vapour field in a widely studied, iso-thermal, benchmark test room, considering the effects of the source size and location. The work provides insight into vapour behaviour within indoor spaces and can have application to fields such as vapour detection, source localisation using autonomous systems, or exposure to toxic chemicals. As an example, we have interpreted the results in terms of current theories of chemical location by animals and the capability of detection dogs.