Accession Number : ADA631885


Title :   Premixed Turbulent Combustion in High Reynolds Number Regimes of Thickened Flamelets and Distributed Reactions


Descriptive Note : Final rept. 15 Mar 2012-14 Mar 2015


Corporate Author : MICHIGAN UNIV ANN ARBOR DEPT OF AEROSPACE ENGINEERING


Personal Author(s) : Driscoll, James F


Full Text : https://apps.dtic.mil/dtic/tr/fulltext/u2/a631885.pdf


Report Date : 24 Mar 2016


Pagination or Media Count : 30


Abstract : The physics of turbulent premixed flames, in the range of the high Reynolds numbers that are associated with Air Force applications, was measured for the first time using advanced laser imaging diagnostics. Combustion in three regimes on the Borghi regime diagram of premixed turbulent flames was quantified for the first time, by imaging the thicknesses of preheat and reaction layers. New PLIF diagnostics were developed, due to our interactions with Dr. Cam Carter at AFRL to image reactions zones with a new CH PLIF method, as well as using the overlap method that involves formaldehyde and OH PLIF. Results are used to assess previous theoretical predictions of regime boundaries. PLIF images of CH, OH and formaldehyde were obtained for thirteen cases. The three regimes are (a) the thickened preheat (TP) regime that is bounded by the Klimov-Williams limit, (b) the broken reaction layers (BR) boundary and the partially-distributed reactions (PDR) regime. A new Hi-Plot burner provides extremely-turbulent flames which is ten times the turbulence level of previous experiments.


Descriptors :   *COMBUSTION , *FLAMES , *LASER DIAGNOSTICS , *REYNOLDS NUMBER , *TURBULENCE , AUGMENTATION , BOUNDARY LAYER , CHEMICAL REACTIONS , CHEMILUMINESCENCE , FORMALDEHYDE , GAS TURBINES , HEAT TRANSFER , LAMINAR FLOW , MATHEMATICAL PREDICTION , MILITARY APPLICATIONS , MIXING , OPTICAL IMAGES , PROPULSION SYSTEMS , REACTANTS(CHEMISTRY)


Subject Categories : Physical Chemistry
      Fluid Mechanics
      Thermodynamics
      Combustion and Ignition


Distribution Statement : APPROVED FOR PUBLIC RELEASE