Experiments on Turbulent Particle-Laden Flows

Summary

Turbulent gas flows containing dilute loadings of solid particles were investigated. These flows occur in many energy and environmental applications including coal combustion, sorbent injection, and material and contaminant transport. A method is presented for simultaneous determination of planar gas and particle velocity fields. The method is applied in streamwise-spanwise planes of a fully developed turbulent channel flow with Reynolds number of 9000 to determine single-point particle and fluid veloc¬ity statistics. Such statistics are employed to test numerical models for particle-laden flows. Additional experiments on flow control are presented in which a piezoelectric actuator is applied to generate normal wall motion at the exit of a turbulent channel. Single-point velocity measurements document the time-averaged flow behavior for several control conditions and demonstrate possibilities for particle control that is either coupled or decoupled with the turbulence. The control method can be applied to alter particle distribution and velocity near and downstream of solid surfaces.