Gas Turbines and Chemical Kinetics
          Coupling chemical kinetics and computational fluid 
              mechanics for engine design
          Kinetically limited processes
                 Nitrogen oxide production
                 Soot formation
                 Flame stability
                 Blow out
                         J Campbell, J. Chambers, Patterns in the sky: natural visualization of aircraft flow fields. NASA SP-                   2
                         514,1994
      Aviation Fuels – Composition
        Carbon Number Distributions                   Hydrocarbon Class Distribution 
                              JP-4                                       n-Parafins
                                                 Cycloparafins
                                    JP-8
                                                                          i-Parafins
                              JP-7
                                               Naphthalenes
                                                                  Alkylbenzenes
            Distillation Temperature
        T. Edwards, L.Q. Maurice, J. Propulsion Power 17 (2001)                       3
          Aviation Fuels – Fuel Variability
            e                                                                       e
            m                                                                       m
                               Fraction of delivered JP-8 fuels with specified properties 
            u                                                                       u
            l                                                                       l
            o                                                                       o
            V                                                                       V
                                                                                     
            l                                                                       l
            a                                                                       a
            t               Aromatics Content                                       t                   Cetane Index
            o                                                                       o
            T                                                                       T
                                                                                     
            f                                                                       f
            o                                                                       o
                                                                                     
            e                                                                       e
            g                                                                       g
            a                                                                       a
            t                                                                       t
            n                                                                       n
            e                                                                       e
            c                                                                       c
            r                                                                       r
            e                                                                       e
            P 40                                                                    P 50
              35
              30                                                                      40
              25                                                                      30
              20
              15                                                                      20
              10                                                                      10
               5
               0                                                                       0
                     12      14      16      18      20       22      24                     36        39       42       45        48       51
                                       Volume %                                                                 Cetane Index
              Significant variability in physical and chemical properties
              Current certification not highly constraining
                   Petroleum Quality Information System Annual Report (2009)
                                                                                                                                                      4
     Surrogate Fuel Concept
     
       Computational fluid                                 Real Diesel
                                       t                   Real Fuel
                                       n
                                       u
       dynamics coupled with           o
                                       m
                                      eA
       detailed chemical kinetics     c
                                      n
                                      a
       requires a simplified fuel     d
                                      n
                                      u          Molecular Weight
                                      b                   Surrogate Fuel
       model                          A                   Surrogate Diesel
                                       t
                                       n
                                       u
                                       o
                                       m
                                       A
                                                 Molecular Weight
                                              Distillation Temperature
      Ideal surrogate fuel must emulate combustion behavior 
       and physical properties of a target real fuel
                                                                       5
     Surrogate Fuels – Previous Work
      Numerous jet fuel surrogate postulations present in 
        literature (e.g.):
          Sarofim et al. ─ Surrogate fuel to model jet fuel pool 
           fires
          Bruno et al. ─ Surrogate fuel to model thermo-physical 
                              properties of jet fuel
        Require detailed characterizations of target fuel 
        (GC, NMR, …)
      Significant uncertainty in chemical kinetics of 
        selected surrogate compounds
         Sarofim et al., Combust. Sci. Tech, 177 (2005) 715–739 
         T.J. Bruno et al., Ind. Eng. Chem. Res 45 (2006) 4371–4380            6