• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.1
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• pp.57-62
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• 2001

EFI system has severe problems of heavy HC emission generated by large fuel droplets and non-uniform air-fuel mixture. Therefore, various atomization techniques are being developed in order to reduce HC emission. The one among those techniques is ar shrouded injector, which has better atomization ability and demands less power loss than other atomizers. Thus, the development of this air shrouded injector can be major topic to cope with international emission regulation. Nevertheless, there are few domestic and foreign studies which deal with air shrouded injector. In this study, the spray characteristics and atomization mechanism of the representative air shrouded injector were analyzed using PDPA system. From experimental results, the definite standards of air shrouded injector's spray characteristics were established.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.6
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• pp.65-71
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• 1999

Recently new engine system is being required to cope with intensive emission restriction . For this reason, GDI(Gasoline direct injection) engine system which can satisfy both as good fuel economy as diesel engine and the performance to surpass PFI gasoline engine is being development . Since fuel injection system plays a significant role in GDI engine performance, the investigation of the spray characteristics injected from GDI injector above all is indispensable for GDI system development. In this study , spray developing shape was visualized using laser sheet with Nd : YAG laser and atomization characteristics was analyzed by measuring velocities and droplet size with PDA. Utilizing these results , the basic design factor of GDI injector can be offered.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2007.11a
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• pp.359-364
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• 2007

Spray characteristics of the APU gas turbine engine were investigated. In order to understand blow out phenomena of the APU engine, we performed fuel spray test. In the test, four operating conditions such as sea level idle, sea level max power, 20,000 feet idle, 20,000 feet max power were used as spray experimental conditions. PDPA(phase Doppler Particle Analyzer) was used for measuring the particle diameter and velocity. Also spray visualization was performed by using ND-YAG sheet laser beam. From the test result, in the case of 20,000 feet idle condition, SMD is about 100 ${\mu}m$ and maximum particle velocity is about 10 m/s. For the flame stability, spray quality should be improved at 20,000 feet idle condition.

• Journal of the Korean Society of Propulsion Engineers
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• v.12 no.1
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• pp.29-36
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• 2008

Spray characteristics for APU gas turbine engine are investigated. In the test, four flight conditions such as sea level idle, sea level max power, 20,000 feet idle, 20,000 feet max power are used as spray experimental conditions. Spray visualization was performed by using ND-YAG laser bean PDPA(Phase Doppler Particle Analyzer) was used for measuring the particle diameter and velocity from 20 mm to 100 mm from discharge orifice. From the test result, SMD is $90{\sim}95\;{\mu}m$ 맛 20,000 ft idle condition and SMD is $60{\sim}75\;{\mu}m$ at sea level idle condition. Also SMD is $55{\sim}65\;{\mu}m$ at 20,000 ft max power condition and SMD is $30{\sim}70\;{\mu}m$ at sea level max power condition. In the case of 20,000 ft idle condition, combustion instability could be occurred due to the higher drop diameter. Therefore it is necessary to decrease the droplet diameter in the high altitude condition.