• 한국신재생에너지학회:학술대회논문집
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• 2011.11a
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• pp.90.2-90.2
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• 2011

This paper describes performance enhancement of a fuel cell's blower by controlling flow path. Different duct diameter at the inlet and outlet of the blower is selected for reducing blower noise level and input power. Hole diameter and the number of hole at the check valve are tested to reduce the input power of the blower. Two types of blower, fuel pressurized blower and cathode blower, are considered in the present study. Throughout experimental measurements of the test blowers, it is found that duct diameter is effective to reduce noise level and input power in the fuel cell blower. Noise reduction due to the optimal duct diameter at the outlet is more effective when flow rate is relatively large. That is, cathode blower has larger noise reduction compared to fuel pressurized blower because of larger flower rate. Input power of the blower can be reduced by controlling the hole diameter and the number of hole at the check valve.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.91-91
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• 2011

This paper describes development procedure of the four types of fuel cell's blowers: pressurized fuel blower, selective oxidation air blower, cathode air blower, and burner air blower. Diaphragm blowers having two heads are selected to maintain force balance when the rotating arms are moving by the driving motor. Dimensions of a diaphragm cavity is designed according to the optimal design procedure using numerical simulation and experimental measurement. Experimental apparatus is designed by considering the bower characteristics having low flow rate and high pressure. Test blower is operated by a diaphragm, which has suction and discharge port on the top of the blower. For analyzing the internal flow of the blower, three-dimensional Navier-Stokes analysis is introduced in the present study. Throughout the optimal design of the blowers, blower performance is enhanced by reducing the unbalance motion of the rotating arm and loss region in the diaphragm cavity.

• 한국신재생에너지학회:학술대회논문집
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• 2007.06a
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• pp.561-564
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• 2007

FCEV uses electric energy which generated from the reaction between Hydrogen and Oxygen in fuel cell stack as driving force. As fossil fuels are exhausted, fuel cell is regarded as a potent substitute for next generation energy source, and thus, most of car-makers make every efforts to develop fuel cell electric vehicle (FCEV). In addition, fuel cell is also beneficial in aspect of environment, because only clean water is produced during chemical reaction process instead of harmful exhausted gas. Generally, Hydrogen is supplied from high-pressured fuel tank, and air blower (or compressor) supply Oxygen by pressurizing ambient air. Air blower which is driven by high speed motor consumes about $7{\sim}8$ % of energy generated from fuel cell stack. Therefore, the efficiency of an air blower is directly linked with the performance of FCEV. This study will present the development process of an air blower and its consisting parts respectively.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2834-2838
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• 2008

An free breathing proton exchange membrane fuel cell (PEMFC) was developed. This paper presents a study of the several effect on the performance of a fuel cell such as air flow rate, opening ratio, and cathode structures. Especially, an air flow rate is critical condition to improve the fuel cell performance. In this paper, we developed a synthetic jet micro air blower to supply high stoichiometric air. The synthetic jet actuation is usually generated by a traditional PZT-driven actuator, which consists of a small cylindrical cavity, orifices and PZT diaphragms. In comparison with free convection fuel cells, the forced-convection fuel cell which equipped synthetic jet micro air blower brings higher performance and stability for long term test. Also, power consumption of the synthetic jet micro air blower is under 0.3W. The results show that the maximum power density was $188mW/cm^2$ at $400mA/cm^2$. The maximum power density was higher 40% than power density of free convection fuel cell.

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.417-420
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• 2006

FCEV uses electric energy generated from the reaction between Hydrogen and Oxygen in fuel cell stack as driving force. As fossil fuels are exhausted, fuel cell is regarded as a potent substitute for next generation energy source, and thus, most of car-makers make every efforts to develop fuel cell electric vehicle (FCEV). In addition, fuel cell is also beneficial in aspect of environment, because only clean water is produced during chemical reaction process instead of harmful exhausted gas. Generally, Hydrogen is supplied from high-pressured fuel tank, and air blower (or compressor) supplies Oxygen by pressurizing ambient air. Air blower which is driven by high speed motor consumes about $7{\sim}8%$ of energy generated from fuel cell stack. Therefore, the efficiency of an air blower is directly linked with the overall performance of FCEV. This study will present developing process of an air blower and its consisting parts respectively.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.197-200
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• 2007

FCEV uses electric energy generated from fuel cell stack, thus all consisting parts must be re-designed to be suitable for electricity based system. Cathode air blower which supplies compressed air into fuel cell stack has similar shape of turbocharger, but a radial turbine of traditional turbocharger is removed and high speed BLDC motor is installed . Generally, maximum 10% of electric power of fuel cell stack is consumed in air blower, therefore an effective design of air blower can improve the performance of FCEV directly. This study will present an aerodynamic design process of an air blower and compare computational results with experimental data.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.67-72
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• 2006

Blower as an air supply system is one of the most important BOP (Balance of Plant) system fur FCV(Fuel Cell Vehicle). For generating and blowing compressed air, the motor of air blower consumes maximum 25% of net power and fuel cell demands a clean air. Considering the efficiency of whole FCV, low friction lubrication of high speed rotor is needed. For the purpose of reducing electrical power and supplying clean air to Fuel cell, oil-free air foil bearings are applied at the each side of brushless motor (BLDC) as journal bearings which diameter is 50mm. The normal power of driving motor has 1.7kW with the 30,000rpm operating range and the flow rate of air has maximum 160 SCFM. The impeller of blower was adopted a mixed type of centrifugal and axial which has several advantages for variable operating condition. The performance of turbo-blower and parameters of air foil bearings was investigated analytically and experimentally. From this study, the performance of the blower was confirmed to be suitable far 80kw PEM FC.

• Proceedings of the KSME Conference
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• 2008.11b
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• pp.2429-2433
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• 2008

A rotary vane blower was developed as an air supply system for fuel cell application. As one way of improving the blower efficiency, a roller was adapted between vanes and cylinder housing. The performance of blower was investigated experimentally. The blower power input was about 115W to compress the air at normal atmospheric condition to 0.2 bar with the flow rate of 140 NLPM, resulting in the blower overall efficiency of 43%. After 400 hours of operation, the performance of blower was not changed. The result showed that developed blower was confirmed to be suitable for fuel cell application.

• The KSFM Journal of Fluid Machinery
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• v.9 no.6 s.39
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• pp.45-53
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• 2006

Turbo-blower as an air supply system is one of the most important BOP (Balance of Plant) systems for FCV(Fuel Cell Vehicle). For generating and blowing compressed air, the motor of air blower consumes maximum 25% of net power, and fuel cell demands a clean air. In this study, turbo-blower supported by air foil bearings is introduced as the air supply system used by 80kW proton exchange membrane fuel systems. The turbo-blower is a turbo machine which operates at high speed, so air foil bearings suit their purpose as bearing elements. Analysis for confirming the stability and endurance is conducted. The rotordynamic stability was predicted using the numerical analysis of air foil bearings and it is verified through experimental works. In spite of various transient dynamic situation, the turbo-blower had stable performances. After the performance test, results are presented. The normal power of driving motor has about 1.6 kW with the 30,000 rpm operating range and the flow rate of air has maximum 160 SCFM. The test results show that the aerodymic performance and stability of turbo-blower are satisfied to the primary goals.

• New & Renewable Energy
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• v.7 no.3
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• pp.29-35
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• 2011

This paper describes an internal flow characteristics of a fuel pressurized blower, used for 1kW domestic fuel cell system. To analyze the flow field inside the diaphragm cavity, compressible unsteady numerical simulation is introduced. SST model with scalable wall function is employed to estimate the eddy viscosity. Moving mesh system is applied to the numerical analysis for describing the volume change of a diaphragm cavity in time. Throughout numerical simulation with the modeling of the inlet and outlet valves in a diaphragm cavity, unsteady nature of an internal flow is successfully analyzed. Force variations on the lower plate of a diaphragm cavity are evaluated in time. It is found that the driving force at the suction stage of a diaphragm cavity is more necessary than that at the discharging stage.