• Transactions of the Korean hydrogen and new energy society
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• v.35 no.2
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• pp.168-174
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• 2024

The electrochemical hydrogen compressor was run under diverse operating conditions in order to probe its capabilities and limitations. It was found that, unlike single-cell operations, the electrochemical hydrogen compressor stack performance improved with a rise in temperature. This improvement in performance was attributed to the gradual weakening of the electro-osmotic drag over time, impacting membrane resistance. As a result of these experiments, compression levels, up to an impressive 120 bar, using the electrochemical hydrogen serial stack were achieved.

• Transactions of the Korean hydrogen and new energy society
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• v.35 no.1
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• pp.75-82
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• 2024

In this study, design parameter exploration based on finite element analysis was performed to find the optimal shape of bellows, the key component of compressor-embedded refueling tank for a newly developed hydrogen refueling station capable of high-pressure charging above 900 bar. In the design parametric study, the design variables took into account the bellows shapes such as contour radius and span spacing, and the response factors were set to the maximum stress and the gap in the contact direction. In the shape design of the compressor bellows for hydrogen refueling station considered in this study, it was found that adjusting the contour span is an appropriate design method to improve the compression performance and structural safety. From the selection of optimal design, the maximum stress was reduced to 49% compared to the initial design without exceeding the material yield stress.

• Transactions of the Korean hydrogen and new energy society
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• v.19 no.1
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• pp.26-34
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• 2008

This study presents an aerodynamic design and an experimental performance test of a turbo air compressor consisted of mixed-flow impeller and curved diffuser for the PEM fuel cell vehicle application. Many studies compare the efficiency, cost or noise level of high-pressure and low-pressure operation of PEM fuel cell systems. Pressure ratio 2.2:1 is considered as design target The goal of compressor design is to enlarge the flow margin of compressor from surge to choke mass flow rate to cover the operational envelope of FCV. Large-scale rig test is performed to evaluate the compressor performance and to compare the effects of compressor exit pipe volume to stall or surge characteristics. The results show that the mixed-flow compressor designed has large flow margin, and the flow margin of compressor configuration with small exit volume is larger than that with large exit volume.

• Transactions of the Korean hydrogen and new energy society
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• v.27 no.2
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• pp.236-243
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• 2016

This paper presents a simple thermo-physical model of reciprocating compressors for household refrigerator-freezers. The compressor model has been developed based on thermodynamic principles and large data sets from the compressor calorimeter tests. The input data are compressor geometry (displacement and clearance volume), compressor speed, suction pressure and temperature, discharge pressure, and ambient temperature. The model can estimate mass flow rate and compressor power consumption within 3.0% accuracy, which is not much larger than measurement errors associated with calorimeter testing under ideal conditions.

• 한국신재생에너지학회:학술대회논문집
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• 2010.11a
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• pp.112.1-112.1
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• 2010

수소경제사회를 위한 수소인프라 구축에서 가장 중요한 부분이 현지설치형 수소스테이션이라고 하겠다. 이러한 수소스테이션은 일본, 미국, 유럽 등 선진각국에서 2015년에 상용화를 계획한 수소연료전지자동차의 보급에 필요불가결한 설비이므로 이들 지역을 중심으로 수요가 발생할 것으로 보인다. 선진국에서는 수소연료전지자동차의 경우 상용화가 이루어지면 2020년경 그 비율은 전체 자동차의 약 5% 수준을 점유할 것으로 보고 있다. 현재 국내에서도 정부주관으로 2015년부터 보급 목표로 수소연료전지차 모니터링연구가 수행되고 있다. 이에 따라 이미 외국 설비를 중심으로 수소스테이션 실증연구가 이루어졌으며, 각 기업체 및 연구기관에서 개질기, 고압압축기, 디스펜서 등 많은 요소기술 개발에 박차를 가하고 있으며, 이 결과로 향후 수소스테이션 국산화에 많은 기여를 할 것으로 사료된다. 아울러 이번 연구는 수소스테이션의 핵심부분인 수소스테이션용 제어로직을 개발하고 시뮬레이터를 제작한 결과에 대해 발표하고자 한다.

• Transactions of the Korean hydrogen and new energy society
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• v.3 no.2
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• pp.1-7
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• 1992

New type of metal hydride heat pump (MHHP) combined with hydrogen compressor was constucted for cooling purpose. A model for calculating the coefficient of performance (COP) is presented for MHHP which consisted of two different stages (enforced and natural stage), and compared with the experimental results. A concept of adiabatic compression work is introduced in the model on the basis of Carnot reversible analysis and the dependence of COP on the various operational parameters is discussed.

• Transactions of the Korean hydrogen and new energy society
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• v.34 no.2
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• pp.141-148
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• 2023

The thermodynamic performance of the electrochemical hydrogen compressor was analyzed to perform a comparative analysis with the performance of the mechanical compressor. The performance was analyzed through the applied current and the measured voltage value. The test results showed that the efficiency of the electrochemical hydrogen compressor was high in the low current density range. In addition, it was confirmed that the amount of increasing compress work of the electrochemical hydrogen compressor is smaller than that of the mechanical compressor. Therefore, it is expected to have higher efficiency than mechanical compression when compressed with a sufficiently high-pressure range.

• 한국신재생에너지학회:학술대회논문집
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• 2009.06a
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• pp.787-790
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• 2009

There are several types of compressors which are appropriate for hydrogen gas station. Metal diaphragm type of hydrogen compressor is the one of them, a use in which satisfies the requirements of maintaining gas purity and producing high pressure over 700 bar. The objective of this study is to investigate an characteristics of compression as bulk modulus of oil varies. Three cases of bulk modulus ranging from $2{\times}10^9$, $4.52{\times}10^9$ and $7{\times}10^9$ were studied through FSI (Fluid Structure Interaction) analysis. Gas pressure, oil pressure and deflection degree of diaphragm were analysed during a certain period of compression process. Highest pressure and deflection were found in the condition of high bulk modulus of $7{\times}10^9$.

• Journal of Power System Engineering
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• v.10 no.4
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• pp.165-171
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• 2006

An experiment to observe reduction of pressure fluctuation in the compressing system utilizing snubber has done. The experiment measured pressure at inlet and outlet of snubber. It used an air compressor as a model of hydrogen one. Snubber with buffer and snubber without buffer were used to get comprehensive comparison between both of that snubber. An analysis by using Fast Fourier Transform (FFT) method was conducted to verify working pressure frequency. With this method pure signal of static pressure was filtered from noisy signal. The experiment was run for several speeds of piston movement. It was controlled by adjustable frequency regulator that controled rotation of actuator motor. This was connected to the piston-reciprocating compressor with V-belt. From result obtained, the fluctuation was increasing proportionally when frequency of driver motor was increased.

• Journal of the Korean Institute of Gas
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• v.17 no.5
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• pp.1-7
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• 2013

In this study, simulation work of HCNG refueling system was performed. The hydrogen was produced from steam reforming process by natural gas. The conversion of natural gas is increased as SCR is increased. but it was no significant difference more than 3 of SCR and fuel throughput is increased as GHSV is increased. Both conversion and fuel throughput levels was optimized when the $1700h^{-1}$ of GHSV. CNG was compressed from low pressure natural gas. For the mixing of $H_2$ and CNG is mixed with the high pressure conditions such as 400bar of $H_2$ and 250bar of natural gas. Single-stage compression was required more power than multi stage. So, multi stage compression was suggested for high pressure compression. We calculated the intermediate pressure to minimize total required power of compressors. The intermediate pressure for $H_2$ and natural gas were derived at 61 and 65 bar, respectively.