Experimental Measurement of Laminar Flame Velocities of LPG–Air …
301
Fig. 4 Flame front propagation in a horizontal tube open at the ignition end [7]
3 Results and Discussion
Experiments at ambient conditions (303 K and 101.325 kPa) were conducted to
measure flame speeds on in-house developed flame tube apparatus. The outcome
of experiments with domestic and calibrated LPG–air mixtures is set out in
Table 1. The average time interval of flame propagation and the average laminar
flame velocity with domestic LPG–air mixture on manual mode was 3.44 s and
0.58 m/s, respectively. However, the sensor-based obtained values stood at 3.39 s
and 0.59 m/s, respectively. The error noted in flame velocity measurement was well
within 2% and acceptable.
The customized calibrated LPG (69.87% propane and 30.13% n-butane)–air
mixtures under manual mode measurement resulted in 3.83 s and 0.52 m/s, respectively. However, the electronic-based measurement recorded 3.80 s and 0.53 m/s,
respectively. A similar type of work by Tripathi et al. [8] with customized LPG
Table 1 Laminar flame speed for LPG–air mixture
Fuel
Oxidizer Manually recorded
Sensor recorded
% error in
flame speed
Time (s)
Flame speed
(m/s)
Time (s) Flame speed
(m/s)
Indian
domestic
LPG fuel
Air
3.48
0.575
3.43
0.583
1.37
3.44
0.581
3.38
0.591
1.69
3.40
0.588
3.36
0.595
1.17
Calibrated
LPG fuel
Air
4.14
0.483
4.10
0.487
0.82
3.61
0.554
3.59
0.557
0.54
3.76
0.531
3.71
0.539
1.48
The fuel and air were operated at an output pressure of 1 bar; Flame propagation test length: 2 m
301
Fig. 4 Flame front propagation in a horizontal tube open at the ignition end [7]
3 Results and Discussion
Experiments at ambient conditions (303 K and 101.325 kPa) were conducted to
measure flame speeds on in-house developed flame tube apparatus. The outcome
of experiments with domestic and calibrated LPG–air mixtures is set out in
Table 1. The average time interval of flame propagation and the average laminar
flame velocity with domestic LPG–air mixture on manual mode was 3.44 s and
0.58 m/s, respectively. However, the sensor-based obtained values stood at 3.39 s
and 0.59 m/s, respectively. The error noted in flame velocity measurement was well
within 2% and acceptable.
The customized calibrated LPG (69.87% propane and 30.13% n-butane)–air
mixtures under manual mode measurement resulted in 3.83 s and 0.52 m/s, respectively. However, the electronic-based measurement recorded 3.80 s and 0.53 m/s,
respectively. A similar type of work by Tripathi et al. [8] with customized LPG
Table 1 Laminar flame speed for LPG–air mixture
Fuel
Oxidizer Manually recorded
Sensor recorded
% error in
flame speed
Time (s)
Flame speed
(m/s)
Time (s) Flame speed
(m/s)
Indian
domestic
LPG fuel
Air
3.48
0.575
3.43
0.583
1.37
3.44
0.581
3.38
0.591
1.69
3.40
0.588
3.36
0.595
1.17
Calibrated
LPG fuel
Air
4.14
0.483
4.10
0.487
0.82
3.61
0.554
3.59
0.557
0.54
3.76
0.531
3.71
0.539
1.48
The fuel and air were operated at an output pressure of 1 bar; Flame propagation test length: 2 m