For this HW, please use the software ANSYS Chemkin-Pro. The files of the complete GRI MECH 3.0 mechanism are attached for the calculations. More information on this mechanism can be found at http://combustion.berkeley.edu/gri-mech/version30/text30.html 1. Plug Flow Reactor Problem (100 pts): Examine the induction times (also known as autoignition delays) for premixed methane-oxidizer mixtures. a) (60 pts) Determine autoignition delays as a function of the initial reactor temperature,T, pressure, p, and equivalence ratio, Q, for CH4-air combustion. Please consider three initial temperatures (1100 K, 1300 K, and 1500 K), two pressure levels (1 atm and 10 atm), and four equivalence ratios (0.3, 0.5, 1.0, and 1.5). This results in a total of 24 possible combinations for (Ti, p, Q). Please use tables and/or plots for comparative analysis. For the case with T = 1500 K, p = 1 atm, Q = 0.5, plot the temperature and species concentrations of some important radicals leading up to the ignition point. Please also explain how you determined the autoignition delay time in your results. b) (40 pts) Examine the sensitivity of autoignition delay to changes in the oxidizer's composition. In part (a), we considered air as the oxidizer. For the case with T = 1500 K, p = 1 atm, Q = 0.5, please repeat the calculation with the following oxidizers (the numbers represent the species mole fractions): 1) O2=1.0 (pure oxygen) 2) O=0.207, N=0.79, O=0.003 (air with O radicals) 3) O2=0.207, N2=0.79, OH=0.003 (air with OH radicals) Compare the results for the different oxidizers, including the corresponding air case from part (a), and explain any important differences you observe.