• 동력기계공학회지
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• 제17권6호
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• pp.5-10
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• 2013

Diesel engines have the advantages of good fuel efficiency and low emissions. Therefore, car makers have been developed various kinds of diesel engine management system to clean up emissions while improving fuel efficiency. One of them is the common rail system. In the common rail system, diesel fuel is injected into the combustion chamber at ultra high pressures up to 1,800 bar to ensure more complete combustion for cleaner exhaust gas, and highly precise multiple injection reduces NOx emission, combustion noise and vibration. Generally speaking, common rail system consists of booster pump, high pressure pump, common rail, injectors, control valves, and sensors. The high pressure pump receives low pressure fuel from the booster pump and supply high pressure fuel to injectors through the high pressure common injection rail. Therefore, high pressure pump has an important role in common rail system. In this paper, we have investigated the performance of high pressure pump of common rail system.

• 동력기계공학회지
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• 제18권6호
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• pp.51-57
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• 2014

High pressure common rail injection technology has revolutionized the diesel industry. Over the last decade it has allowed engine builders to run higher injection pressures as much as above 1,300bar in order to increase engine efficiency, while reducing emissions. This common rail system has low pressure circuit which is consist of low pressure pump, cascade overflow valve and flow metering unit. The low pressure pump's purpose is to feed fuel oil to the high pressure pump. The cascade overflow valve keeps pressure in front of the metering unit constant and provides lubrication for the high pressure pump. The metering unit, known as the MPROP or fuel pressure regulator, regulates the maximum flow rate delivers to the rail. In this paper, we have investigated the performance characteristics of each components and total low pressure circuit of common rail system.

• 전기학회논문지
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• 제56권10호
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• pp.1751-1756
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• 2007

This paper presents a high performance pressure control scheme for SR(Switched Reluctance) type hydraulic oil pump using DITC(Direct Instantaneous Torque Control). SR drive has a good feature for pump applications due to a high efficiency, high speed and high torque characteristics. But, SR drive has high torque ripple in commutation region. So, the pump pressure variation is high in the region. In order to reduce the pressure variation, DITC combined with pressure control scheme is presented in this paper. A simple PI controller with flow and pressure limit, generates a reference torque to keep the constant actual pump pressure. The direct torque controller of SR drive generates inverter switching signals according to a control rule and a torque estimator. Computer simulation and experiemtal results show the validation of the proposed control scheme.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2000년도 유체기계 연구개발 발표회 논문집
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• pp.75-81
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• 2000

Experimental studies on the characteristics of annular jet pump were carried out in this paper. The effects of high pressure chamber on the characteristics of annular jet pump were sought in this paper. Experiments were done for three shapes of high pressure chamber, and for several lengths of the high pressure chamber. Three types of the high pressure chamber's entrances($90^{\circ}$ single inflow, $45^{\circ}$ single inflow, and $45^{\circ}$ double inflow) were tested. Water was used for both the primary fluid and secondary fluid. The results obtained in this study are as follows; $45^{\circ}$ double inflow type is the most effective among the tested three types of the high pressure chamber's entrances. The efficiency of jet pump with 400mm of high pressure chamber length is the highest among the chamber lengths tested in this study, thus indicating appropriate chamber length is required to get an efficient jet pump.

• 한국수소및신에너지학회논문집
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• 제34권1호
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• pp.59-68
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• 2023

In this study, the performance of high-pressure fuel pumps was compared to find a high-pressure pump suitable for dimethyl ether (DME) fuel, and to establish a database of basic data on flow rates. The use of DME in compression ignition engines can reduce pollutant emissions. The cetane value of DME is higher than that of diesel fuel. The physical properties of DME are similar to liquefied gasoline gas (LPG), and when pressurized at a pressure of 6 bar or more, it changes from gas to liquid. Two types of high pressure pumps used in this study were independent injection type pump and a wobble plate type pump. Two high-pressure pumps with different injection types were compared. By measuring and comparing the performance changes of the two high-pressure pumps, a pump suitable for DME was selected and performance improvement measures were proposed. The changed experimental conditions to measure the performance change of the high pressure pump were increased in the units of 100 to 1,000 rpm and 100 rpm, and the experiment was performed at common rail pressures 300 and 400 bar. it was confirmed that the DME inside the fuel supply system remained in a liquid state through temperature sensors, pressure sensors, and pressure gauges. As a result of the experiment, it was confirmed that the flow rate discharged from the high-pressure fuel pump increased as the motor rotational speed increased, and the flow rate of the high-pressure fuel pump

• 한국해양공학회지
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• 제27권6호
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• pp.106-111
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• 2013

In this study, numerical simulations and performance evaluation has been carried out to investigate performance characteristics of air-type high pressure piston pump. ANSYS and CFX were applied for analyzing the structure and flow behavior of air-type high pressure piston pump, respectively. The performance evaluation of high pressure piston pump was performed experimentally, the results were compared with simulation. It was found that the freezing phenomenon was improved by 20% and the pressure fluctuation decreased by 50%, compared with the previous pump.

• 수산해양기술연구
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• 제35권4호
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• pp.428-434
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• 1999

Experimental studies on the characteristics of annular jet pump were carried out in this paper. Jet pump can be used widely for the transportation of solid materials, farm produce and fishes. The effects of high pressure chamber on the characteristics of annular jet pump were sought in this paper. Experiments were done for three shapes of high pressure chamber, and for several lengths of the high pressure chamber. Three types of the high pressure chamber's entrances($90^{\circ}$ single inflow, $45^{\circ}$single inflow, and $45^{\circ}$ double inflow) were tested. Water was used for both the primary fluid and secondary fluid. The results obtained in this study are as follows; $45^{\circ}$double inflow type is the most effective among the tested three types of the high pressure chamber's entrances. The efficiency of jet pump with 400mm of high pressure chamber length is the highest among the chamber lengths tested in this study, thus indicating appropriate chamber length is required to get an efficient.

• 한국화재소방학회논문지
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• 제30권2호
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• pp.106-113
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• 2016

초고압 용적형 펌프는 로터의 회전에 의한 주기적인 용적의 변화를 이용하는 펌프로 고압, 고유량을 동시에 만족하며 로터의 저속 및 고속 회전에 따라 변화 없이 일정하게 상대적으로 높은 펌프 효율을 유지할 수 있는 장점을 가진다. 많이 사용되고 있는 원심펌프와는 달리 별도의 진공펌프가 없이도 자흡 성능을 가지고 있으며, 비교적 단순한 구조로 인하여 경량화, 소형화가 가능한 특성을 자기고 있다. 유체를 높은 압력으로 이송할 수 있으며, 압력의 변동에 따라 유량의 변동이 적은 정량 토출이 가능하다. 이러한 용적형 펌프를 사용하는 이유는 흡입된 유체가 유량의 변화 없이 토출되는 장점이 있기 때문이다. 본 연구에서는 유량의 변화가 없다는 장점이 있는 용적형 펌프의 체절시스템을 개발하여 펌프의 고압 운전시의 안전성을 확보하고자 하였다. 체절시스템은 컨트롤러 프로그램, 전자클러치, 릴리프밸브의 3가지로 이루어져, 한 가지 시스템이 작동하지 않아도 다른 시스템이 작동하는 시스템으로 이루어져 있다. 컨트롤러 프로그램과 전자 클러치의 작동을 확인하기 위한 과속도 시험과 릴리프 밸브의 유체유동해석, venting 실험을 통해 현재 개발한 초고압 용적형 펌프의 체절시스템이 작동됨을 확인하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2012년도 추계학술대회 논문집
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• pp.592-596
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• 2012

This paper presents numerical analysis result of rotor-bearing system of a multi-stage high pressure pump. Especially resonance possibility, stability and damping factor are estimated for a selected commercial multi-stage high pressure pump. The result shows that it is not easy to avoid resonance of rotor-bearing system against main excitation forces which are residual unbalance force and pressure pulsation. This makes damping effect be more important.

• 융복합기술연구소 논문집
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• 제4권2호
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• pp.61-65
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• 2014

Pressure distribution around rotating impeller blades in centrifugal pump has been main issue for design of efficient and high performance automotive water pump. In addition, pressure losses of inlet water pipes should be considered to reduce additional pressure drop and design high performance engine cooling system. In this paper, pressure distribution inside water pump and pressure drop between inlet and outlet of water pump are investigated numerically to design plastic water pump for clean diesel engine application. And the inlet geometry of water pump was considered to analysis the effect of inlet water pipe geometry on pressure distribution around impeller blades and outlet pressure. The prediction results are compared with experimental data to validate and determine optimal operation condition without water pump cavitation. Major design parameters such as blade angle, volute geometry, system pressure, and coolant flow rate are considered to confirm applying possibility of plastic blades to the clean diesel engine.