Large Eddy Simulation of Air Escape through a Hospital Isolation Room Single Hinged Doorway—Validation by Using Tracer Gases and Simulated Smoke Videos

Saarinen, Pekka E.; Kalliomäki, Petri; Tang, Julian W.; Koskela, Hannu

The purpose of this paper is to report a CFD LES simulation in one example case, to aid in assessing the accuracy of the CFD approach and to introduce the computer modeled, multilayered, smoke videos. The door parameters varied in the laboratory experiments were opening-time, hold-open time, closing-time, and opening-angle. It was noted then that reducing the opening-speed (in the absence of ventilation) resulted in larger AVM, or that the effect of increased duration overrode the effect of faster door movement. Moreover, without passage the air escape through the doorway continued at nearly constant speed up to the longest holdopen time tested (25 s). A similar effect has been found by Hathway et al. [37] who studied doorway flows generated by a single hinged-door in a small-scale water tank model. The effect of opening angle (90°vs 45°tested) was smaller, but clearly detectable. By contrast, the effect of a 2°C temperature difference between the two rooms resulted in 41% increase in the AVM in the case used in the CFD simulation [35] .