Abstract
A downward flow of glass bead particles in a vertical pipe is investigated using a two-component LDV/PDPA for a range of Re (6400 < Re < 24,000) and a constant particle loading (m = 0.7). Two particle sizes of 70 and 200 μm are considered in the present work. For the 70 μm particles, the presence of the particles dampens the gas-phase turbulence intensity at the lowest value of Re investigated (8300) compared with the single-phase flow at the same Re. As Re increases, the gas turbulence increases, and for Re > 13,800 the gas turbulence is enhanced compared with the single-phase flow at the same Re. For the 200 μm particles, the intensity also increases with Re and is enhanced for all values of Re investigated, except at the lowest value of Re investigated (6400). At this value, the gas turbulence is equal to that of single-phase flow at the same Re. The observed trend in the gas-phase turbulence modulation with Re is proposed to be due to the change in the segregation patterns and in the average volume fractions of the particles with increasing Re. More importantly, the present experimental results suggest that, consideration of either the gas and particle characteristic length scales or the particle Reynolds number solely is insufficient to predict gas-phase turbulence modulation in gas-particle flows.
| Original language | English |
|---|---|
| Pages (from-to) | 416-434 |
| Number of pages | 19 |
| Journal | International Journal of Multiphase Flow |
| Volume | 31 |
| Issue number | 4 |
| DOIs | |
| Publication status | Published - Apr 2005 |
| Externally published | Yes |
ASJC Scopus Subject Areas
- Mechanical Engineering
- General Physics and Astronomy
- Fluid Flow and Transfer Processes
Keywords
- Gas-particle flow
- Granular flow
- LDV
- Reynolds number
- Turbulence modulation