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In: Mechanical Engineering

1. A premixed stoichiometric methane-air flame has a laminar flame speed of 0.33 m/s and a...

1. A premixed stoichiometric methane-air flame has a laminar flame speed of 0.33 m/s and a temperature of 2200 K. The reactants are initially at 300 K and 1 atm. Find the velocity of the combustion products relative to the flame front and the pressure change across the flame. Assume that the reaction goes to completion and there is no dissociation.

2. Repeat Problem 1 for a premixed stoichiometric methanol-air flame. The flame speed is 0.48 m/s and the flame temperature is 2000 K.

3. For methane, the maximum laminar flame speed in pure oxygen is 11 m/s, whereas in air the maximum flame speed is 0.45 m/s. Explain what causes this increase in the flame speed.

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