The Effect of Oxygen Concentration on Ignition of Fuel Spray in Low-Pressure Air Flow

1985 ◽  
Vol 107 (1) ◽  
pp. 18-23
Author(s):  
Y. H. Zhao ◽  
N. K. Chen ◽  
J. S. Chin
Keyword(s):  
Oxygen Concentration ◽  
Low Pressure ◽  
Fuel Spray ◽  
Thermal Ignition ◽  
Oxygen Injection ◽  
Stagnant Region ◽  
Oxygen Addition ◽  
Effect Of Oxygen ◽  
Ignition Improvement ◽  
Local Oxygen

Further experimental research has been carried out on the ignition improvement by oxygen addition in a small pilot combustion chamber taken from an existing aeroengine. Both uniform mixture method and local oxygen injection method have been investigated. The results show that oxygen addition improves low-pressure ignition performance significantly. Local oxygen injection makes much better use of oxygen added. Experimental results show low evaporation percentage of fuel spray responsible for the poor ignition performance. Based on thermal ignition theory, a semianalytical equation has been obtained to predict the relative enlargement of maximum ignition velocity by oxygen addition, the equation can correlate experimental data very well. To form a stagnant region with suitable oxygen concentration is the most important factor in the design of ignitor with oxygen addition.

The Effect of Oxygen Concentration on Ignition of Fuel Spray in Low Pressure Air Flow

1984 ◽  
Author(s):  
Y. H. Zhao ◽  
N. K. Chen ◽  
J. S. Chin
Keyword(s):  
Oxygen Concentration ◽  
Low Pressure ◽  
Fuel Spray ◽  
Oxygen Injection ◽  
Stagnant Region ◽  
Aero Engine ◽  
Oxygen Addition ◽  
Effect Of Oxygen ◽  
Ignition Improvement ◽  
Local Oxygen

Further experimental research has been carried out on the ignition improvement by oxygen addition in a small pilot combustion chamber taken from an existing aero-engine. Both uniform mixture method and local oxygen injection method have been investigated. The results show that oxygen addition improves low pressure ignition performance significantly. Local oxygen injection makes much better use of oxygen added. Experimental results show low evaporation percentage of fuel spray responsible for the poor ignition performance. Based on thermal ignition theory, a semi-analytical equation has been obtained to predict the relative enlargement of maximum ignition velocity by oxygen addition, the equation can correlate experimental data very well. To form a stagnant region with suitable oxygen concentration is the most important factor in the design of ignitor with oxygen addition.

Influence of Oxygen on Microstructures of Ti-Mo-Cr Alloy

2014 ◽  
Vol 896 ◽  
pp. 613-616 ◽  
Author(s):  
Junaidi Syarif ◽  
Eko Kurniawan ◽  
Mohd Rasidi Rasani ◽  
Zainuddin Sajuri ◽  
Mohd Zaidi Omar ◽  
...  
Keyword(s):  
Oxygen Content ◽  
Oxygen Concentration ◽  
Solid Solution Hardening ◽  
Stable Phase ◽  
Powder Metallurgy Method ◽  
Β Phase ◽  
Α Phase ◽  
Phase Calculation ◽  
Oxygen Addition ◽  
Effect Of Oxygen

In this study, the effect of oxygen addition on the microstructures of Ti-18%Mo-10%Cr alloy was investigated. The alloy was fabricated by a powder metallurgy method. The samples were subjected to sintering at 1300°C for 4 hours and furnace cooling. A Bo-Md method was initially applied for predicting stable phase. Calculation using the Bo-Md method showed that Ti-18%Mo-10%Cr alloy have bcc (β) phase at ambient temperature. All samples with various oxygen contents exhibited needle-like structures within equiaxed grains. The increase of oxygen content promoted formation of porosity in the α phase. Calculation of phase stability using JMatProTM showed that the decrease of β phase’s stability was not due to formation of the α phase on sintering, but due to promotion of nucleation and grain growth of diffusional α phase upon furnace cooling. It was also shown that vol.% of porosity of the alloy slightly increased with increasing oxygen content. Therefore, the increase of oxygen concentration could accelerate the formation of α phase and reduce the alloy’s density. The hardness increased as the oxygen concentration increased. The increase of the hardness might be due to combination of the solid solution hardening of oxygen and the precipitation hardening of α phase.

The Effect of Oxygen Addition on Oxidation Resistance and Cutting Performance of Si3N4 Ceramics

2007 ◽  
Vol 534-536 ◽  
pp. 1089-1092
Author(s):  
Mituyoshi Nagano ◽  
Hideaki Sano ◽  
Shigeya Sakaguchi ◽  
Guo Bin Zheng ◽  
Yasuo Uchiyama
Keyword(s):  
Bending Strength ◽  
Cutting Tools ◽  
Cutting Performance ◽  
Al2o3 Content ◽  
High Wear Resistance ◽  
Composition Analysis ◽  
Performance Improvements ◽  
Oxygen Addition ◽  
Effect Of Oxygen ◽  
Si3n4 Ceramics

The effect of oxygen addition on oxidation behavior of the β-Si3N4 ceramics with 5 mass% Y2O3 and 2 or 4 mass% Al2O3 was investigated by performing oxidation tests in air at 1300° to 1400°C and cutting performance tests. These tests were intended to clarify their ware resistance as cutting tools. The results of mass change, SEM observation and composition analysis of the specimens before and after oxidation test showed that as the Al2O3 content in the β-Si3N4 ceramics increased, mass changes resulted higher oxidation during which process pores and cracks formed due to the release of N2 gas. The values of hardness and bending strength of the specimens with relatively small amount of 2 mass% Al2O3, which formed solid solution in the Si3N4 structure [Si6-zAlzOzN8-z (z = 0.1)], showed larger than those of the specimen with 4 mass% Al2O3 (z = 0.2). The specimens group added with Al2O3 of 2 mass% (Z = 0.1) also showed high wear resistance. From this, we could conclude that the mechanical properties of β-Si3N4 ceramics depending on oxygen introduction is much effective on cutting performance improvements of the cutting performance of β-Si3N4 ceramics.

scholarly journals Effect of Oxygen Concentration on the Detection of Mercury in an Atmospheric Microwave Discharge

1999 ◽  
Vol 38 (Part 1, No. 7B) ◽  
pp. 4595-4600 ◽  
Author(s):  
Kamal Hadidi ◽  
Paul P. Woskov ◽  
Guadalupe J. Flores ◽  
Kareen Green ◽  
Paul Thomas
Keyword(s):  
Oxygen Concentration ◽  
Microwave Discharge ◽  
Effect Of Oxygen

Effect of oxygen concentration and temperature on ignition time of polypropylene

2012 ◽  
Vol 110 (1) ◽  
pp. 485-487 ◽  
Author(s):  
Jozef Martinka ◽  
Karol Balog ◽  
Tomáš Chrebet ◽  
Emília Hroncová ◽  
Janka Dibdiaková
Keyword(s):  
Oxygen Concentration ◽  
Ignition Time ◽  
Effect Of Oxygen
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