Evaluations of wall shear stress in the standpipe of a circulating fluidized bed
Shear stress was obtained in the standpipe of a Circulating Fluidized Bed (CFB) for a light cork particles under a variety of flow conditions. The shear stress data were estimated using incremental gas phase pressure drop readings, and an estimate of the bed height to predict the hydrostatic pressure drop [(dp/dy) = ρs (1-ε) g+4τsw/D]. In addition, we have also obtained data on aeration rate in the standpipe, particle circulation rate and riser gas flow rate. Analysis of the results using a one-dimensional momentum equation reveal that the observed forced per unit area may be attributed to wall friction. The resulting shear stress demonstrates that as the aeration air in the standpipe was increased the shear at the wall was decreased. An attempt was made to model solids friction factor as a function of particle velocity and it was compared to the other literature correlations.
- Research Organization:
- National Energy Technology Laboratory (NETL), Pittsburgh, PA, Morgantown, WV, and Albany, OR
- Sponsoring Organization:
- USDOE - Office of Fossil Energy (FE)
- OSTI ID:
- 935167
- Report Number(s):
- DOE/NETL-IR-2008-156; NETL-TPR-1773
- Country of Publication:
- United States
- Language:
- English
Similar Records
Prediction of Solids Circulation Rate of Cork Particles in an Ambient-Pressure Pilot-Scale Circulating Fluidized Bed
Impact of the Circulating Fluidized Bed Riser on the Performance of a Loopseal Nonmechanical Valve