Separation Control in a Conical Diffuser by Vortex Generator Jets

Vortex shedding in a two-dimensional diffuser: theory and simulation of separation control by periodic mass injection

We develop a reduced-order model for large-scale unsteadiness (vortex shedding) in a two-dimensional diffuser and use the model to show how periodic mass injection near the separation point reduces stagnation pressure loss. The model estimates the characteristic frequency of vortex shedding and stagnation pressure loss by accounting for the accumulated circulation due to the vorticity flux into...

Conical Flow induced by Quenched QCD Jets

Quenching is a recently discovered phenomenon in which QCD jets created in heavy ion collisions deposit a large fraction or even all their energy and momentum into the produced matter . At RHIC and higher energies, where that matter is a strongly coupled Quark-Gluon Plasma (sQGP) with very small viscosity, we suggest that this energy/momentum propagate as a collective excitation or “conical flo...

A Comment on Conical Flow Induced by Heavy-Quark Jets

The suppression of high transverse momentum particles, recently discovered at RHIC, is commonly interpreted as due to parton energy loss. In high energy nuclear collisions, QCD jets would deposit a large fraction of their energy and into the produced matter. The question of how this energy is degraded and whether we can use this phenomenon to probe the properties of the produced matter is now u...

Closed-loop Control of Vortex Shedding in a Separated Diffuser Using an Inverse Method

We propose a closed-loop control algorithm for vortex shedding in a separated diffuser. We introduce pulses of zero-net-mass injection (consecutive blowing and suction) together with an inverse vortex imaging method. This method estimates the circulation of a vortex in the separated region based on pressure at a limited number of observer points at the wall. The closed-loop algorithm determines...

Flow control over a tractor-trailer using vortex generator