An advanced fluid visualisation technique, particle image velocimetry, was employed to investigate the hydrodynamic properties of particles and aggregates. The experiments were conducted in a settling column filled with a suspension of fluorescent polymeric beads as flow tracers. A thin vertical section of the settling column was illuminated by a laser sheet, while the motions of particles were recorded by a high speed CCD camera. Large solid spheres, flocs of latex microspheres and aggregates of marine diatoms were characterised for their hydrodynamic properties. The trajectories of the tracer particles were tracked when a large particle or aggregate settled through the suspension of the tracers, which gave the streamlines surrounding the falling object. The streamlines demonstrate directly the curvilinear feature of the interaction between approaching particles. However, the available curvilinear model underestimates the collision frequency function of particles by one order of magnitude or two. The collision potentials of the flocs and aggregates are more than an order of magnitude greater than the similar-sized solid spheres. Algal aggregates appear to be highly porous and fractal with a fluid collection efficiency of 10–40%, which would significantly enhance the flocculation between particles and the mass transfer into the aggregates.
Skip Nav Destination
Article navigation
Research Article|
July 01 2007
Investigation of the hydrodynamic behaviour of particles and aggregates by particle image velocimetry (PIV) Available to Purchase
F. Xiao;
1Department of Civil Engineering, The University of Hong Kong, Pokfulam Rd., Hong Kong, China (E-mail: [email protected]; [email protected])
E-mail: [email protected]
Search for other works by this author on:
X.Y. Li;
X.Y. Li
1Department of Civil Engineering, The University of Hong Kong, Pokfulam Rd., Hong Kong, China (E-mail: [email protected]; [email protected])
Search for other works by this author on:
K.M. Lam
K.M. Lam
1Department of Civil Engineering, The University of Hong Kong, Pokfulam Rd., Hong Kong, China (E-mail: [email protected]; [email protected])
Search for other works by this author on:
Water Supply (2007) 7 (2): 213–220.
Citation
F. Xiao, X.Y. Li, K.M. Lam; Investigation of the hydrodynamic behaviour of particles and aggregates by particle image velocimetry (PIV). Water Supply 1 July 2007; 7 (2): 213–220. doi: https://doi.org/10.2166/ws.2007.056
Download citation file:
Sign in
Don't already have an account? Register
Client Account
You could not be signed in. Please check your email address / username and password and try again.
Could not validate captcha. Please try again.
eBook
Pay-Per-View Access
$38.00