Chemical Kinetics

Chemical Kinetics

Details

​Gas turbine and engine design are rapidly evolving to tackle the issues of pollution, global warming, and fuel flexibility. A predictive design capability is essential in optimizing the performance of energy devices to achieve high efficiency and low emissions. Such designs rely on a number of physical models, of which chemical kinetics plays a very critical role. The chemical kinetic mechanism of a fuel relies on a database of experimental values over a range of temperatures and pressures. These data include ignition delay time, fuel reactivity, elementary reaction rates, and species time-history profiles. 

Our laboratory has the following facilities for chemical kinetics studies:
1) Low pressure shock tube​
2) High pressure shock tube
3) Rapid compression machine

Shock tubes and RCM can provide well-defined​ temperatures and pressures for kinetics investigations that cover broad regimes of engineering and scientific interest. They can be used to achieve temperatures of 500-5000 K and pressures from sub-atmospheric to 500 atm. Chemical kinetics measurements performed behind reflected shock waves have near-instantaneous heating times, spatially uniform mixtures, and occur in near-stationary flows. These facilities are coupled with non-intrusive, species-specific, quantitative laser diagnostics developed concurrently in our laboratory to carry out novel chemical kinetics research. The figure below shows the range of pressures and test times achievable with the three facilities. 
Pressure vs Test Time
Below is a brief listing of projects currently being pursued:
  1. Future fuel formations - this collaborative project with Saudi Aramco is exploring strategies and experimental campaigns to propose fuel formulations suitable for future engines
  2. Ignition delay time measurements are being carried out for a variety of pure fuels and blends: propene, iso-butene, 2,5 dimethyl hexane, 4-methyl heptane, tri-methyl benzenes, FACE (Fuels for Advanced Combustion Engines) gasolines and diesels, naphtha, etc. 
  3. Laser-based species time-histories are being measured for a variety of reference fuels and fuel blends. The species being measured include CO, CO2, H2O, OH, C2H4, C2H2, CH4, and H2O2. 
  4. Rate constant (k) - experiments are planned to measure rate constants for a number of critical elementary reactions. This includes Fuel + OH --> Products and reactions involving H2O2 and HO2.