• Transactions of the Korean Society of Mechanical Engineers B
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• v.36 no.12
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• pp.1185-1192
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• 2012

The typical operating temperature of an automotive fuel cell is lower than that of an internal combustion engine, which necessitates a refined strategy for thermal management. In particular, the performance of the cooling module has to be higher for a fuel cell system because the temperature difference between the fuel cell and the surrounding is lower than in the case of the internal combustion engine. Even though the cooling system of an automotive fuel cell determines the operating temperature and temperature distribution of the fuel cell, it has attracted little research attention. This study presents the mathematical model of a cooling system for an automotive fuel cell system using Matlab/$Simulink^{(R)}$. In particular, a radiator model is developed for design optimization from the development stage to the operating stage for an automotive fuel cell. The cooling system model comprises a fan, pump, and radiator. The pump and fan model have an empirical relation, and the dynamics of the pump and fan are only explained by motor dynamics. The basic design study was conducted, and the geometric setup of the radiator was investigated. When the control logic was applied, the pump senses the coolant inlet temperature and the fan senses the coolant out temperature. Additionally, the cooling module is integrated with the fuel cell system model so that the performance of the cooling module can be investigated under realistic operating conditions.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.816-821
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• 2002

It is getting more important that energy efficiency and manufacturing cost of the electric motor in appliance. The SRM has been alternative choice. But acoustic noise and harshness in this motor was widely known. So this paper had been studied on the noise reduction of a SRM in air conditioner. This works include some parameters regarding to blown noise sources like a reluctance torque ripple, air gap eccentricity, Especially, it was focused on dynamic characteristics of the system based on mechanical viewpoint. It came to successful results. Besides, this gave us a validity of phase excitation in experimental measurements.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2003.06a
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• pp.942-945
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• 2003

Noise cause is dividing to fluid noise by exhaust flow of fan and vibration noise by rotational vibration of motor. Until now, measuring method has been used to measure vibration by the accelerometer, this method has been not measured for the vibration in some parts of brush and commutator because of motor construction. This research was purposed on the accurate analysis. using laser vibration analyzer, of noise cause against the difficult part in old times. By using this measured data, we would like to use for the design of silent motor.

• Proceedings of the Safety Management and Science Conference
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• 2010.04a
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• pp.347-357
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• 2010

본 논문은 QFD(Quality Function Development)기법을 활용하여 소비자의 요구사항을 반영한 음식물 처리기의 핵심 품질 요소를 도출하는데 목적을 두었다. 일반 소비자와 관련업계 종사자를 대상으로 설문조사와 FGI를 실시하여 VOC(voice of customer)를 도출하였고, 전문가 그룹을 통해 EC를 도출하여 VOC와 EC(Engineering Characteristic)간의 상관관계를 도표화 하여 HOQ(House Of Quality)를 작성하였다. HOQ 차트를 통해 분쇄건조식 음식물 처리기에 있어 우선시 되는 것은 음식물 분쇄기능, 건조기능 외에 냄새 배출기능, 외관 색상 등의 요소가 중요한 품질요인이라는 결과을 도출하였다. 부품별 요인으로는 분쇄 탈수와 관련 된 모터와 냄새 제거와 관련한 팬모터가 가장 핵심 부품으로 고려되어야 한다는 결과를 도출하였다.

• Journal of the Korean Society for Precision Engineering
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• v.29 no.7
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• pp.793-798
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• 2012

Oil gear pump is used for the cooling pump system of commercial vehicle. The hydraulic pulsation pressure of oil gear pump is one of the most important reasons for the vibration and noise of the pump. In this study, the several hydraulic factors acting on oil gear motor are analyzed by CFD in operation of cooling system. Forced vibration analysis due to hydraulic pulsation pressure is analyzed by FEA for predicting deformation and equivalent stress.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2001.11a
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• pp.512-516
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• 2001

It is recent trend that the manufactures of refrigerator use BLDC motor which RPM is changed by voltage of DC power, instead of induction motor in order to reduce energy consumption and noise radiation. It can be controlled two or more RPM suitable to environmental condition. For example it is operate much lower RPM than normal(usual) in the night. This paper introduce the method of noise control in the case of using BLDC Fan motor for refrigerator.

• Proceedings of the SAREK Conference
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• 2007.06a
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• pp.79-79
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• 2007

• Transactions of the Korean Society of Automotive Engineers
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• v.23 no.2
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• pp.153-160
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• 2015

Hybrid Electric Vehicles(HEVs) have seriously come into prevalence recently as car manufacturers and consumers have become more aware of the environmental and economic problems of conventional vehicles. For the alternative power-train and battery cooling systems in HEVs, an effective thermal management system is required, and many automakers are interested in using Brushless DC(BLDC) motors for cooling fans for the overall traction unit's performance and energy saving capability. This paper presents the development status of BLDC motors as major parts of the power-train, i.e. the engine cooling and battery cooling fans of HEVs. A design that uses BLDC motors for the power-train and each battery cooling fan, is successfully implemented through using electro-magnetic analysis, and prototype BLDC motors are examined. As experimental results, the BLDC motors achieved an efficiency of 85% as engine cooling fans and 72% as a battery thermal management fan motor. The electric cogging noise is significantly reduced by changing the skew of the slot pitch angle and optimizing the magnetic shape.

• The KSFM Journal of Fluid Machinery
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• v.20 no.1
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• pp.5-14
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• 2017

A fan-motor assembly in a vacuum cleaner is analyzed through system-level analysis method. This system consisted of three components, a fan, motor, and the flow resistance of the motor, or of the vacuum cleaner. System-level analysis method is characterized by the combination of torque matching at a constant throttling condition between the fan and the motor and the pressure drop at a constant flow rate due to the flow resistance of the motor, or of the vacuum cleaner. The performance characteristics of the fan-motor assembly and the vacuum cleaner system could be predicted over the whole range of operation, based on the characteristics of each component. The predicted performance of the vacuum cleaner system through system-level analysis agreed well with the experimental results within 4.5% difference of pressure and 6% difference of the efficiency. The effect of flow resistance of a motor is investigated and it is found that the efficiency decrease of fan-motor assembly at the constant flow rate due to the flow resistance of a motor is determined by the flow resistance ratio(FRR), which is defined as a ratio of flow resistance of motor and the flow resistance of a constant throttling condition of a given point. The fan-motor assembly(S2 model) was modified to reduce the FRR from 9.0% to 2.4% and the experimental result shows that the efficiency of S2 model was improved by about 3% at best efficiency point.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.21 no.12
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• pp.656-662
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• 2009

In this paper, the heat resistance reliability of an axial smoke exhaust fan was investigated. An axial smoke exhaust fan should be capable of operating at $250^{\circ}C$ for 2 hours. The heat resistance reliability was evaluated by the heat resistance reliability test. A B10 life with a 90% confidence level was estimated to be about 48 minute. The failure occurred in the motor due to high temperature. The main failure mechanisms of the motor were melting of bond and insulating paper and burning of insulating materials in the coil. The heat resistance reliability was improved by changing the way to unite the core and the coil and by replacing the insulating paper and the insulating materials of the coil. A B10 life with a 90% confidence level of a modified axial smoke exhaust fan was estimated to be over 120 minute.