Experimental and numerical characterization of the flowfield in the large-scale UW live fire research facility

Recently, a large‐scale (19.5m × 15.4m × 12.8m) live fire research facility (LFRF) has been built at the University of Waterloo with the capabilities of conducting controlled and systematic experimental studies to investigate the behaviour of large fuel spill fires in crosswinds. The present work is focused on characterizing the wind generated by banked fans and the flowfield in the LFRF using experimental techniques and large eddy simulation (LES). Two configurations are examined: the empty enclosure and the enclosure with a large blocking object (cylinder) aligned perpendicular to the flow direction. Detailed velocity measurements are provided throughout the facility. The experimental results show that the flowfield inside the empty enclosure is consistent with the behaviour of a bluff wall jet. Three‐dimensional LES are performed for the same two configurations. The experimental velocity profiles are used to set the inflow conditions in the calculations. The numerical predictions are all within the experimental uncertainty in the core region for the empty enclosure. For the case with the cylinder, the size of the wake is very well reproduced by the simulations and the shedding frequency corresponds to the value given in published experimental studies of a flow over free standing cylinders. The present LES model is also capable of predicting more detailed flow characteristics such as the stagnation and recirculation region, compared with what was achievable in the large‐scale experiments. In the wake the time‐averaged velocities from the LES results are overpredicted. Possible sources of discrepancy are discussed. Copyright © 2008 John Wiley & Sons, Ltd.