E. Hontanon et al., The CAESAR code for aerosol resuspension in turbulent pipe flows. assessment against the storm experiments, J AEROS SCI, 31(9), 2000, pp. 1061-1076
The aim of this work is the development of a new model of aerosol resuspens
ion in turbulent pipe flows, which is based on the force balance concept. T
he model considers both types of aerodynamic forces, drag and lift forces,
and properly balances these forces with the frictional and adhesive forces.
Original aspects of the new model are that it takes into account the reduc
tion of the adhesive force due to the surface roughness and the random incr
ease of the lift force above its mean value due to the fluctuations of the
turbulent flow. The resuspension model has been implemented in a computer c
ode. CAESAR, and its performance has been verified against several experime
nts of the STORM programme. In the experiments, the velocity of the how pas
sing over the deposits was increased stepwise. Significant particle entrain
ment was observed at the beginning of each velocity stage. Then, resuspensi
on decreased sharply and became practically zero after a few tens of second
s. This behaviour was correctly reproduced with CAESAR, although the durati
on of the period of strong resuspension predicted with the code was shorter
than the one measured in the experiments. The faster resuspension predicte
d with CAESAR is due in part to the fact that the code models the resuspens
ion of monolayer deposits in which all particles are exposed to the flow, w
hich is not the case of the STORM experiments. (C) 2000 Elsevier Science Lt
d. All rights reserved.