• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2000년도 유체기계 연구개발 발표회 논문집
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• pp.351-358
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• 2000

In a small centrifugal compressor system, a high-speed motor needs to be developed to drive impellers directly. Heat is generated by both electrical heating due to copper coil resistance and aerodynamic heating in the gap between the rotor and stator in a high-speed motor. Removal of the heat is essential to the design of such motors since most magnetic materials are brittle and can be easily fractured by the heat. In the present study the cooling flow fields and temperature distributions were analyzed by using computational fluid dynamics simulation for a high-speed motor which has air cooling system as well as water cooling system. In the analysis a conjugate heat transfer problem is solved by considering both convective heat transfer in the cooling system and conduction heat transfer in solid parts. Based on design drawings of a motor, air cooling system and water cooling system were analyzed to obtain temperature field and thus to check the coiling system performance. Also the cooling performance are studied for various flow rates of cooling air and water at the inlets.

• 한국전산구조공학회논문집
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• 제29권1호
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• pp.1-8
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• 2016

본 논문에서는 원심식 대형 압축기 구동용 모터 베이스 프레임의 구조해석 및 콘크리트 타설에 따른 구조안전성 평가를 수행하였다. 먼저 모터 베이스 프레임에 적용되는 네 가지 하중조건에 따른 구조해석을 진행하고 최대 비틀림 에너지 이론 및 Mohr-Coulomb 이론을 통하여 구조안전성을 평가하였다. 구조해석 결과에서 취약한 구조안전성을 나타낸 연결부 등의 불연속적인 부분에서 발생하는 국부응력에 대하여 ASME VIII Div. 2에 따른 구조안전성 평가를 적용함으로써 좀 더 합리적으로 구조안전성 평가를 수행할 수 있었다. 또한, 모터 베이스 프레임 내부에 콘크리트 타설 및 미타설에 따른 구조해석 및 ASME 구조안전성 평가를 통하여 모터 베이스 프레임의 구조안전성을 정량적으로 비교하여 콘크리트 타설로 인한 구조 안전성의 향상을 확인하였다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2001년도 춘계학술대회논문집
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• pp.936-941
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• 2001

This paper deals with the design of oil-tree motor-driven two-stage centrifugal compressor supported by air-lubricated multi-leaf foil bearings. The design of this compressor is performed, based upon prediction of critical speeds, load capacity, and stability. It is demonstrated in this paper that multi-leaf foil bearings can be adopted to satisfactorily support this centrifugal compressor.

• 전력전자학회논문지
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• 제26권4호
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• pp.298-301
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• 2021

A mechanical angle estimator is presented in this study to achieve the sensorless control of permanent magnet synchronous motor (PMSM) used in driving a reciprocating compressor. Braking the PMSM at a specific mechanical angular position is critical for the silent stoppage of the reciprocating compressor. The performance of conventional mechanical angle observers used in reciprocating compressor drives can be seriously affected according to gains of the speed controller because such observers rely on the magnitude of current ripples. A speed ripple-based mechanical angle estimator is proposed to solve this problem. Experimental results showed the effectiveness of the proposed method.

• 항공우주기술
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• 제8권1호
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• pp.98-107
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• 2009

5MW급 발전용 가스터빈을 개발하기 위해 주요 구성품 중의 하나인 압축기의 성능을 시험 평가하고자 하며, 이를 위한 사전 작업으로 압축기 시험 리그의 진동 특성을 분석하여 압축기 운전시 구동 방법에 대한 정보를 확보하였다. 압축기 시험 설비는 입 출구 배관과 시험부 및 구동부로 구성되어 있고, 특히 구동부와 시험부에서 가속도계를 이용하여 진동 특성을 계측하였다. 압축기 주 하우징과 콜렉터, 베어링캐리어, 토크미터, 기어박스, 전동 모터 등에 가속도계를 장착하여 진동 속도 및 주파수 분석을 수행하였다.

• 설비공학논문집
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• 제13권8호
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• pp.763-770
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• 2001

The high pressure side rotary compressor is investigated in this study. The temperatures at 29 points of main components and the refrigerant and the performance of the instrumented compressor are measured at various operating conditions. The complex heat transfer mechanism between the components, such s cylinder, suction pipe and stator of motor, is fairly clarified. It is also confirmed that the achievement of a high efficiency by reducing the heat transfer loss in the rotary compressor is possible.

• 유체기계공업학회:학술대회논문집
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• 유체기계공업학회 2003년도 유체기계 연구개발 발표회 논문집
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• pp.697-703
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• 2003

For a single stage two cylinder rotary compressor, an analytical study has been made on the discharge gas pulsation. Discharge system of the twin rotary compressor consists of lower and upper mufflers and connecting passage holes between them, and cavities on both sides of the motor and passages between them. Acoustic modeling for the discharge system by transfer matrix method gives acoustic impedances at discharge valves so that gas pulsation at the valve sections can be obtained from discharge mass velocity. Since the mass velocity and the pressure pulsation at the valves are affected by each other, iteration should be made for convergence. Gas pulsations at other sections can also be calculated by using transfer matrix.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 1999년도 추계종합학술대회
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• pp.482-485
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• 1999

본 논문에서는 80196KC 마이크로프로세서에 의해 제어되는 공기압축기의 원격감시제어시스템을 제안한다. 제안된 모니터링시스템에서는 RS-232 직렬 통신에 의해 원거리에서 운전되는 공기압축기를 조작하고, 그 운전 상태에 대한 데이터 확인 및 이상유무를 감시한다. 단상유도전동기에 의해 구동되는 공기압축기 시스템을 대상으로 실험한 결과 그 타당성을 확인하였다.

• 한국안전학회지
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• 제21권5호
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• pp.12-16
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• 2006

This paper deals with the noise evaluation and noise reduction of a reciprocating air-compressor. The reciprocating air-compressor is widely used in the small and medium sized industrial firms, many employees exposed and irritated by their noise in the workplace. Thus, appropriate noise control actions should be taken to prevent hearing loss due to the its noise exposure. Lead-wrapping techniques are employed to identify the contribution of principal noise sources which are generally known to be motor, belts, suction valves, discharge valves, moving parts, and flow-induced noise caused by edges or discontinuities along the flow path including expansions, contractions, junctions and bends. As a result, the main noise sources of the air-compressor are categorized by the suction and discharge noise, valve noise, and compressed air tank noise. Based on the investigations, mufflers are designed to reduce both the suction and discharge noise and the compressed-air tank noise. Instead of the conventional valve plate, polyethylene resin is used the reduction of valve impact noise. In addition, attempts are made to reduce the valve noise propagation to the cylinder head and the compressor tank by using the insulation casings. As a result of the countermeasure plans, a noise reduction up to 10dB(A) could be achieved for the air-compressor.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2003년도 추계학술대회논문집
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• pp.478-485
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• 2003

Today, although there have been high technical developments of a compressor in the respect of its capacity, it has been so hard to develop in the respect of vibration and noise because mechanical structure of it has originally numerous vibration and noise. However, if we can grasp the point of systematic phenomena of vibration and noise through the understanding of dynamic characteristics in mechanical equipment, it may be possible to consider countermeasures. In this study about a reciprocal compressor, the part of its machinery is modeled as rigid body, and the part of its spring is modeled as flexible body, and then they are analyzed by DADS. Each rigid body and spring are connected with joint torque of a motor is applied to shaft, and pressure is applied to a piston so that a compressor can be revolved. Based on this modeling, influence of a compressor's vibration is analyzed through changes of offset, connecting rod and crank radius In the case of weight balance, it I produced after re-design, and then changes of vibration of a compressor's inside are checked through experiments. These analysis data may help set measures of reducing vibration of a reciprocal compressor.