• 제목/요약/키워드: Exhaust air

검색결과 1,335건 처리시간 0.026초

Numerical Study on the Air-Cushion Unit for Transportation of Large-Sized Glass Plate

  • Jun, Hyun-Joo;Kim, Kwang-Sun;Im, Ik-Tae
    • 반도체디스플레이기술학회지
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    • 제6권1호
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    • pp.59-64
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    • 2007
  • Non-contact transportation of a large-sized glass plate using air cushion for the vertical sputtering system of liquid crystal display (LCD) panel was considered. The objective of the study was to design an air pad unit which was composed of multiple injection and exhaust holes and mass flow supplying pipe. The gas was injected through multiple small holes to maintain the force for levitating glass plate. After hitting the plate, the air was vented through exhaust holes. Complex flow field and resulting pressure distribution on the glass surface were numerically studied to design the air injection pad. The exhaust hole size was varied to obtain evenly distributed pressure distribution at fixed diameter of the injection hole. Considering the force for levitating glass plate, the diameter of the exhaust hole of 30 to 40 times of the gas injection hole was recommended.

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직분식 예혼합 압축착화 디젤엔진의 운전조건과 연료조성에 따른 연소 및 배기 특성 (The Characteristics of Combustion and Exhaust Emission according to Operating Condition and Fuel Composition in a Direct Injection Type HCCI Diesel Engine)

  • 이기형;류재덕;이창식
    • 한국자동차공학회논문집
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    • 제12권1호
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    • pp.10-16
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    • 2004
  • The Homogeneous Charge Compression Ignition (HCCI) engine has advantage for reducing the NOx and P.M. simultaneously. Therefore, HCCI engine is receiving attention as a low emission diesel engine concept. This study was carried out to investigate the characteristics of combustion and exhaust emission for operating conditions in a direct injection type of HCCI engines such as supercharged and naturally aspirated using diesel fuel and additive. From the experimental result, we found that cool flame was always appeared and also it was difficult to control combustion characteristics by changing the injection timing in HCCI. In addition, at the lean air-fuel ratio and high speed range, it was observed that charging air pressure, additive or increasing intake air temperature is effective to increase combustion performance and reduce exhaust emission. We concluded that chemical reaction by the increasing intake air temperature or additive without physical improvement has limitation for reduction of exhaust emission.

대형디젤엔진의 오염물질 배출특성 (Characteristics of Exhaust Emissions from a Heavy-duty Diesel Engine)

  • 엄명도;류정호;이종태;임철수
    • 한국자동차공학회논문집
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    • 제7권9호
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    • pp.20-27
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    • 1999
  • The proportion of diesel vehicle is very high in this country . PM and NOx emitted from diesel-posered vehicle is severely ;affecting to be air quality . Especially, diesel particulate matters(DPM) including black smoke are hazardous air pollutants to human health and environment. In order to reduce the exhaust emissions from diesel engines, it is necessary to analyze the characteristics of exhaust emissions from diesel engines in various driving conditions. Recently, there are occasion to increase the fuel consumption rate to engine power up. So, in this study we have tested a diesel engine detached from in use -diesel vehicle and analyzed exhaust emission by driving condition and fuel dispersion rate. From this results, we will prepare the comprehensive management plan for exhaust emissions from diesel vehicles and contribute to the improvement of air pollution in urban area.

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Effects of Drying Methods Based on Exhaust Cycle and Time on the Quality and Drying of Red Peppers

  • Nam, Sang Heon;Ha, Yu Shin;Kim, Tae Wook
    • Journal of Biosystems Engineering
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    • 제39권2호
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    • pp.101-110
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    • 2014
  • Purpose: The purpose of this study is to develop a system to optimize drying potential energy of the exhausted hot air by changing relative humidity of the air. This study modified the conventional drying method into a drying method changing exhaust cycle and time in order to control the relative humidity of the exhausted hot air during drying process. Method: A valve on the vent was controlled according to a preset time to change the exhaust cycle and time. This study analyzed the influence of the two different types of drying method on the drying characteristics, required energy, and quality of the dried peppers: conventional drying method exhausting hot air continuously and new drying method controlling exhaust cycle and time. Results: Drying characteristics based on exhaust time showed that drying time increased with exhaust time, and specific energy consumption was reduced by 28% from 18.39 MJ/kg (conventional method) to 13.24 MJ/kg when exhaust time was set to one minute. Drying characteristics based on heating time showed that drying time increased with heating time and specific energy consumption was reduced by 30% from 18.39 MJ/kg (conventional method) to 12.87 MJ/kg when exhaust time was set to 22 minutes. Drying characteristics based on exhaust cycle showed that drying time increased with exhaust cycle, and specific energy consumption was reduced by 31% from 18.39 MJ/kg (conventional method) to 12.69 MJ/kg when exhaust time was set to one minute and exhaust cycle was set to 22 minutes before drying and 40 minutes after drying. The quality of the dried red peppers showed that capsaicin, color, and sugar content were high as 34.87 mg/100g, 66.33, and 11.87%, respectively, when exhaust time was set to one minute and exhaust cycle was set to 22 minutes before drying and 40 minutes after drying. Conclusions: In order to utilize the drying potential energy of the exhausted air during drying process, the conventional drying method was modified into the drying method controlling exhaust cycle and time. The results showed that drying with exhaust cycle of one minute was more efficient in terms of drying time, required energy, and quality of the dried peppers than the one with exhaust cycle of 20~40 minutes.

COMPARISON OF HYDROCARBON REDUCTION IN A Sl ENGINE BETWEEN CONTINUOUS AND SYNCHRONIZED SECONDARY AIR INJECTIONS

  • Chung, S.-H.;Sim, H.-S.
    • International Journal of Automotive Technology
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    • 제3권1호
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    • pp.41-46
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    • 2002
  • Effect of secondary air injection (SAI) on hydrocarbon reduction has been investigated in a single cylinder Sl engine operating at cold-steady/cold-start conditions. The hydrocarbon emission and exhaust gas temperature with and without catalytic converter were compared with continuous and synchronized SAIs, which injected secondary air intermittently into exhaust port. Effects of SAI location, SAI pressure, SAI timing, and location of catalytic converter have been investigated and the results are compared for both SAls with base condition. At cold-steady condition, the rate of HC reduction increased as the location of SAI was closer to the exhaust valve for both synchronized and continuous SAls. The emission of HC decreased with increasing exhaust-A/F when it was rich, and was relatively insensitive when it was lean. The timing of SAI in synchronized SAI had significant effect on HC reduction and exhaust gas temperature and the synchronized SAI was found to be more effective in HC reduction and exhaust gas temperature compared to the continuous SAI . At cold-start condition, when the catalytic converter was located 20 cm downstream from the exhaust port exit, the catalytic converter warm-up period for both SAls decreased by about 50%, and the accumulated hydrocarbon emission during the first 120 s decreased about by 56% and 22% with the synchronized and continuous SAIs, respectively, compared to that of the base condition.

선박용 소각로 이젝터의 배출온도 변화에 따른 유동과 배기특성 (The Stream and Exhaust Gas Characteristics for Variation of Exhaust Gas Temperature of Marine Incinerator Ejector)

  • 김태한
    • 한국해양공학회지
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    • 제14권2호
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    • pp.60-64
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    • 2000
  • An experimental study was performed to investigate the optimal ejector and operating condition of vessel incinerator. Exhaust gas temperature and secondary air which makes vacuum pressure at ejector throat regions were considered as an important factor. According to the measurement of pressure temperature and nitrogen oxides between non combustion and combustion we found the stream and exhaust gas characteristics of incinerator. This results can give us the exhaust gas temperature control system air pollutant reduction method and the optimum ejector design.

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강제배기를 이용한 굴삭기 공기조화 시스템에 관한 연구 (A Study on Air-Conditioning System for Excavator using Forced Exhaust)

  • 황지현;정찬세;고주현;양순용
    • 드라이브 ㆍ 컨트롤
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    • 제10권2호
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    • pp.23-29
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    • 2013
  • The excavator is used in a variety of construction environments. There are many kinds of risk like falling rocks or harmful dust. The excavator cabin protects the operator not only from these harmful environments but also provides a comfortable working environment. By the way, the excavator cabin consumes a lot of energy for cabin air conditioner. For this reason, the research is required to reduce energy consumption. This study suggests the air conditioning system for excavator using forced exhaust. First, the forced exhaust system simulated by AMESim tool and surveyed the applicability. Using AMESim simulation, it was investigated the effect of cabin inside temperature by intake flow rate and intake air temperature. The experiment executed using the 1.5 ton excavator and field tested according to the intake flow rate. Finally, verified the applicability on the air conditioning system for excavator using forced exhaust.

신경회로망을 이용한 정상상태에서의 자동차 엔진의 공연비제어 (Air-Fuel Ratio Control of Automobile Engines in Steady States by Neural Networks)

  • 최종호;원영준;고상근;노승탁
    • 대한기계학회논문집
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    • 제16권11호
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    • pp.2119-2125
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    • 1992
  • 본 연구에서는 현재 사용되고 있는 산소센서의 단점을 극복할 수 있는 방법을 광역공연비센서처럼 공연비를 추정할 수 있는 방법을 연구한다. 그 방법으로 신경회 로망을 사용한 배기가스의 공연비 추정기(estimator)를 구성한다. 그리고 이 추정기 를 이용한 공연비 제어기를 설계하고 실제 MPI엔진에 적용하여 그 성능을 알아 보겠다.

실외기 토출 유량 증대를 위한 Shroud 형상 및 휀 위치 최적 설계 (Optimization of Shroud Shape and Fan Location for Increasing Exhaust Flow Rate of Air Conditioner Outdoor Unit)

  • 유기정;김유일;이관수;차우호
    • 설비공학논문집
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    • 제21권11호
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    • pp.599-605
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    • 2009
  • This paper presents a numerical evaluation of the flow rate of air conditioner outdoor unit by investigating the effects of fan location and shroud shape. To determine optimal design parameters, we investigated the exhaust flow rate by changing shroud height, fan height, fan guide height, and fan width. The 3rd order central composite design was performed to select three most important parameters affecting the exhaust flow rate. According to the result of response surface method, the exhaust flow rate of the optimum model increased by 6.25% compared to that of the base model.

조명발열 배기시스템의 배기위치에 따른 배기열량 실험연구 (A Study of Exhaust Air Flow for Cooling Load Reduction from Interior Lighting)

  • 오병길;정민호;원종서;이훈
    • 설비공학논문집
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    • 제25권1호
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    • pp.1-6
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    • 2013
  • This study aims to reduce cooling energy by grasping kinds of heating load in building in order to decrease cooling energy in summer and eliminate efficiently heating load. Lighting heating value was confirmed through examination and experiment concerning lighting heating and reducible exhaustion value was extracted lighting apparatus. The optimal exhaust system by air conditioning type was suggested for applying lighting heat exhaust system and the method contributing to promotion supplying low energy architecture was suggested by predicting reduced cooling load.