Question

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.

Need help please.

Solutions

Expert Solution


Related Solutions

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...
Methane is burning with minimum amount of air to form the stable products. The premixed methane-air...
Methane is burning with minimum amount of air to form the stable products. The premixed methane-air mixture is filled in a leak-proof spherical vessel at an initial pressure of 1 bar and 298 K. The vessel is well insulated to avoid thermal energy interaction with the surroundings.The combustible mixture is ignited at the centre of the vessel using an electrical spark. The energy added to the mixture for ignition is negligible. During the combustion process, the pressure of the combustion...
1. Calculate the adiabatic flame temperature for the following mixtures initially at 298 K: stoichiometric butane-air...
1. Calculate the adiabatic flame temperature for the following mixtures initially at 298 K: stoichiometric butane-air mixture, stoichiometric butane-oxygen mixture, 2.0% (by volume) of butane in air. Use enthalpies of formation and heat capacities from the NIST Chemistry WebBook, which can be found at http://webbook.nist.gov/chemistry/. 2) Repeat the adiabatic flame temperature calculation without the restriction on the possible products using an online version of the CEA calculator developed by NASA and located at http://www.grc.nasa.gov/WWW/CEAWeb/ceaHome.htm. Compare the results of the two...
A plane has a heading relative to the air of speed 121 m/s and direction 23.5°...
A plane has a heading relative to the air of speed 121 m/s and direction 23.5° East of North. The air is moving relative to the ground with wind speed 49 m/s and direction 33.4° North of West. a) If the plane is flying at an altitude of 5560 m and drops a package directly above a city, what distance away from the city will the package land? (b) If the plane begins a journey from one city to another...
For a constant-volume stoichiometric propane-air mixture initially at 298K, determine the adiabatic flame temperature and final...
For a constant-volume stoichiometric propane-air mixture initially at 298K, determine the adiabatic flame temperature and final pressure assuming constant specific heats evaluated at 298K.
Calculate the adiabatic flame temperature for the following mixtures initially at 298 K: stoichiometric butane-air mixture,...
Calculate the adiabatic flame temperature for the following mixtures initially at 298 K: stoichiometric butane-air mixture, stoichiometric butane-oxygen mixture, 2.0% (by volume) of butane in air. Calculate without the restriction on the possible products using an online version of the CEA calculator developed by NASA and located athttp://www.grc.nasa.gov/WWW/CEAWeb/ceaHome.htm. Compare the results of the two calculations and explain possible differences.
1. Consider a simplified one-dimensional laminar flame, such as that discussed in the classroom. The earliest...
1. Consider a simplified one-dimensional laminar flame, such as that discussed in the classroom. The earliest description of a laminar flame is that of Mallard and Le Chatelier in 1883. Assume that: a. 1-D, constant area, steady flow, b. kinetic and potential energies, viscous shear work, and thermal radiation are neglected, c. pressure is constant, d. diffusion of heat and mass are governed by Fourier’s and Fick’s laws and binary diffusion is applied, e. Lewis number is unity, f. individual...
a plane is going East at a speed relative to the air of 160 m/s. a...
a plane is going East at a speed relative to the air of 160 m/s. a 30.0 m/s wind is blowing toward the south while the plane is traveling. The velocity of the plane to a ground observer is:
A jet is flying with an air speed of 500 m/s. A parcel is dropped out...
A jet is flying with an air speed of 500 m/s. A parcel is dropped out of the plane. Assume that it takes 40 seconds for the parcel to hit the ground.. Assume no air resistance.a. How high is the jet?b. How far forward horizontally from the spot where it leaves the jet, does the parcel move during those 40 seconds?c. Where is the parcel relative to the jet?
1. Methane and oxygen exist in a stoichiometric mixture at 500 kPa and 298 K. They...
1. Methane and oxygen exist in a stoichiometric mixture at 500 kPa and 298 K. They are ignited and react at constant volume. Combustion is complete. a. Find the heat removed from the system per kmol of fuel if the final products are at 1500 K. b. What is the final pressure? c. Explain what assumptions made in this calculation are less accurate for constant volume combustion than for the constant pressure combustion we have studied before. d. If the...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT