• 제목/요약/키워드: 유압서보 인젝터

검색결과 4건 처리시간 0.02초

3개 구동방식(SI, PI, DPI)별 디젤HEV용 인젝터의 분무 특성 비교 (Comparison on Spray Characteristics of Diesel HEV Injectors for 3-different Driving Type (SI, PI, DPI))

  • 정명철;성기수;김상명;이진욱
    • 한국분무공학회지
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    • 제19권1호
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    • pp.9-14
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    • 2014
  • Performance of DI diesel engine with high-pressure fuel injection equipment is directly related to its emission characteristics and fuel consumption. So, the electro-hydraulic injector for the common-rail injection system should be designed to meet the precise high fuel delivery control capability. Currently, most high pressure injector in use has a needle driven by the solenoid coil energy or the piezo actuator controlled by charge-discharge of output pulse current. In this study, macroscopic spray approaching method was applied under constant volume chamber to research the performance of three different injectors : solenoid, indirect-acting piezo and direct-acting piezo type for CR direct-injection. LED back illumination for Mie scattering was applied on the liquid spray visible of direct-acting piezo injector, including hydraulic-servo type solenoid and piezo-driven injectors. As main results, we found that a direct-acting piezo injector had better a spray tip penetration than hydraulic-servo injectors in spray visualization.

구동방식이 다른 서보유압형 인젝터의 분사응답성 연구 (Study on Injection Response of Servo-Hydraulic Injector with Different Actuation Method)

  • 권지원;정명철;이진욱
    • 한국분무공학회지
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    • 제18권2호
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    • pp.87-93
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    • 2013
  • In this paper, high-pressure injection characteristic of servo hydraulic injector as the key component of diesel CRDi system, which is driven by solenoid and piezo-actuator were examined by experimental analysis. High-pressure injection characteristic of standard diesel fuel injected at high pressure up to 160 MPa was investigated at high-pressure chamber by using a high-speed camera for spray visualization and quantitative analysis. By this study, we found that the piezo-driven injector has better performances in controlling the fuel injection with the high pressure, including fuel quantity, spray penetration length and spray velocity, than that of a solenoid-driven injector. In particular, the needle response time for start of injection in piezo-driven injector was faster of about $125{\mu}s$ than that of solenoid-driven injector. Consequently, it is known that the piezo-driven injector has more degrees of freedom in controlling the fuel injection with the high pressure than solenoid-driven injector.

3-way형과 Bypass형 서보유압 피에조 인젝터의 구동특성 비교 (Comparison Analysis of Dynamic Characteristics of Servo-hydraulic Piezo-driven Injector between 3-way and Bypass-circuit Type)

  • 조인수;정명철;이진욱
    • 한국자동차공학회논문집
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    • 제21권5호
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    • pp.169-175
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    • 2013
  • CRDi technology of diesel engine was developed from in the early 2000s due to a need to increase fuel efficiency and environment care. Especially, high-pressure fuel injection system in CRDi system which has a fuel injection unit including an injector, a fuel pump and common-rail, etc. becomes possible to make the exhaust gas clean as well as power improvement. In this study, comparison of dynamic characteristics of servo-hydraulic piezo-driven injector with 3-way and bypass-circuit type was analyzed by using the AMESim code. As results of this study, it found the bypass-circuit inside servo-hydraulic piezo injector can cause a faster injection response than that of the 3-way type. Also it was shown that bypass-circuit type had better control capability due to hydraulic bypass system.

직접구동 피에조 인젝터의 CRDi 단기통 디젤엔진 연소 특성 분석 (Analysis on Combustion Characteristics of CRDi Single-cylinder Diesel Engine with Direct Needle-driven Piezo Injector)

  • 정명철;성기수;김상명;이진욱
    • 한국자동차공학회논문집
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    • 제22권5호
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    • pp.108-115
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    • 2014
  • In this study, experimental approaching method was applied under and single-cylinder engine to research the performance of direct needle-driven piezo injector (DPI) for CR direct-injection. As key-point factor of this DPI that relies on direct-acting operating of injector needle, unlike conventional hydraulic-servo, its nozzle needle can be directly driven by piezo actuator. Thus, effect of direct-acting injection of DPI on diesel combustion and emission characteristics was investigated under common-rail single-cylinder direct-injection engine, equipped with three different driving mechanism, including indirect-acting solenoid, piezo and DPI system. As main results, it found that a direct-acting piezo injector has higher of IMEP. And it has higher heat release rate during premixed combustion and mixing controlled combustion phase due to its higher heat release, even though nitrogen oxide (NOx) formations were increased slightly.