Mixing dynamics in pulsed fuel jets

Add to your list(s) Download to your calendar using vCal

• Dr Edward Richardson, University of Southampton
• Friday 29 May 2015, 13:00-14:00
• LR5, Inglis Building, CUED..

If you have a question about this talk, please contact Antoine Debugne.

The effects of split-injection on the mixing and the fluid residence time distribution in turbulent gaseous jets are investigated using Direct Numerical Simulation (DNS). The mixing physics identified in this study are important for the understanding of split-injection compression-ignition engine operation, in which mixing rates and fuel residence time control the rate of heat release and pollutant formation. The configuration involves a round turbulent jet issuing from a flat plate, subject to single-pulse, double-pulse, and continuous injection. A novel analysis of fluid residence time is performed by solving a transport equation for the fluid age. A similarity scaling is determined for the residence time in the continuous jet case. It is then shown that the radial gradients of the age of injected fluid are greater in the continuous jet suggesting that, in continuous fuel injection, entrainment of older more-reacted fluid provides a mechanism to promote ignition further upstream compared to pulsed jets. The implications of scalar dissipation and entrainment rate transients for combustion are discussed.

This talk is part of the Fluids Group Seminar (CUED) series.

This talk is included in these lists:

• Acoustics Lab Seminars
• Engineering Department Acoustics/Combustion Student seminars
• Fluids Group Seminar (CUED)
• LR5, Inglis Building, CUED.

Note that ex-directory lists are not shown.