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A premixed laminar flame is stabilized in a one - dimensional gas flow where the vertical velocity, v ( cm / s ) , of

A premixed laminar flame is stabilized in a one-dimensional gas flow where the vertical velocity, v (cm/s), of the unburned mixture varies with the horizontal coordinate, x (cm), according to the following equation. A in the equation is used to assess different multiples of the laminar flame speed. In this equation L is half of the burner horizontal opening. For this problem, consider L=1 cm. ASL- v =5,+(454,-54): Consider propane (at Tu =400 K, P =2 atm) combustion in air at an equivalence ratio of 1.1. Use the experimentally determined laminar flame speeds correlations determined by Metghalchi and Keck as follows: Y B Tu SL = Sl,ref Turef)( P Prer (1-2.1 Yait) SL,ref = BM + B2C0-M)2 y =2.18-0.8(0-1) B =-0.16+0.22(0-1) These relations were developed relative to 298 K and 1 atm. For propane, M =1.08, BM =34.22 cm/s, and B2=-138.65 cm/s. Complete the following steps. A) Determine the laminar flame speed for propane at the given conditions. (8 points) B) Determine the distribution of the local angle of the flame surface from vertical for A=1.1,2,3,4, and 5. Display your results by plotting the local angle vs. horizontal distance, X.(8 points) CAssuming the flame speed is independent of position and constant for all cases, determine the flame shape. Display your results by plotting the flame shape (z) vs. horizontal distance (x), scaling your figures so that 1 mm on the x-axis is the same size as 1 mm on the z-axis. (12 points) D) Describe the results of part B and C in your own words, referring to the plots developed. What is the impact of increasing the flow rate? (7 points)
A premixed laminar flame is stabilized in a one-dimensional gas flow where the vertical velocity, v(cms), of the unburned mixture varies with the horizontal coordinate, x(cm), according to the following equation. A in the equation is used to assess different multiples of the laminar flame speed. In this equation L is half of the burner horizontal opening. For this problem, consider L=1cm.
v=SL+(ASL-SLL)x
Consider propane (at Tu=400K,P=2atm ) combustion in air at an equivalence ratio of 1.1. Use the experimentally determined laminar flame speeds correlations determined by Metghalchi and Keck as follows:
SL=SLref(TuTu,ref)(PPref)(1-2.1Ydil)
SLref=BM+B2(O-O?M)2
=2.18-0.8(O-1)
=-0.16+0.22(O-1)
These relations were developed relative to 298K and 1atm. For propane, O?M=1.08,BM=34.22cms, and B2=-138.65cms. Note, Ydil is the mass fraction of diluent present (if any) in the air-fuel mixture. Complete the following steps.
A) Determine the laminar flame speed for propane at the given conditions. (6 points)
B) Determine the distribution of the local angle of the flame surface from vertical for A=1.1,2,3,4, and 5. Display your results by plotting the local angle vs. horizontal distance, x.(6 points)
C) Assuming the flame speed is independent of position and constant for all cases, determine the flame shape. Display your results by plotting the flame shape (z) vs. horizontal distance (x), scaling your figures so that 1mm on the x-axis is the same size as 1mm on the z-axis. (9 points)
D) Describe the results of part B and C in your own words, referring to the plots developed. What is the impact of increasing the flow rate? (4 points)
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