Suscripción a Biblioteca: Guest

ISSN Online: 2377-424X

ISBN Print: 0-89116-559-2

International Heat Transfer Conference 8
August, 17-22, 1986, San Francisco, USA

DIFFUSION CONTROLLED DEPOSITION OF PARTICULATE MATTER FROM FLOWING SLURRIES

Get access (open in a dialog) DOI: 10.1615/IHTC8.3710
pages 2573-2579

Sinopsis

Investigations have been carried out to determine the rate of deposition of micron sized magnetite particles from flowing slurry onto the inner walls of simulated heat exchanger tubes. Slurry was circulated in a closed-loop facility with deposition measurements being made In an aluminium tube of 19mm bore. Runs were conducted under isothermal conditions at temperatures between 293K and 350K over a Reynolds Number range 9,600 to 147,000. Slurry concentration was maintained in the range 200 to 600 mg/kg. The average magnetite particle size as measured on a Coulter Counter was approximately 1.5 μm. Deposit growth on the test section was measured by means of a low energy X-ray machine.
The results showed high initial deposition rates accompanied by steadily increasing removal rates producing asymptotic curves. Analysis indicates that deposition is governed by the forced convective diffusion of particles to the tube wall. Correlation of deposition rates is possible using standard mass transfer equations. Deposits were friable and porous with void fractions ≈70%.