On the two-way interactions between dispersed particles and turbulent flows
Said Elghobashi
Mechanical and Aerospace Engineering Department, University of California, Irvine
Abstract:
Particle-laden turbulent °ows are ubiquitous in nature (e.g. dust storms on Earth and Mars) and in industrial applications (e.g. liquid fuel and pulverized coal sprays in combus-
tion chambers). Experimental and numerical studies of these °ows are quite challenging due to the wide spectra of length- and time-scales of the dispersed particles in addition
to the spectra of scales intrinsic to the carrier °uid turbulence. The two-way nonlinearinteractions between the dispersed particles and the turbulence result in complex multi-
scale physical phenomena.
The lecture focuses on the physical mechanisms of the two-way interactions between dispersed spherical particles and simple turbulent °ows using Direct Numerical Simu-
lation (DNS). Particles whose diameter is smaller than the Kolmogorov length scale of turbulence are simulated as point particles. Results of particle-laden isotropic and ho-
mogeneous shear turbulent °ows are presented.
Particles with diameter larger than the Kolmogorov length scale are fully resolved using the Immersed Boundary method. Results of fully resolved particle-laden isotropic
turbulence are presented.