• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.542-545
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• 2008

Experiments have been performed to investigate effects of pulsating cathode flow on a 10-cell proton exchange membrane fuel cell (PEMFC) stack. For all the experiments, the flow rate, temperature and relative humidity of hydrogen at the anode inlet are fixed. The effects of the pulsating frequency, amplitude and flow rate at the cathode inlet on performance of 10-cell PEMFC are examined. The polarization and power curves show that the power output and limiting current is substantially increased when the pulsating component is added to cathode flow channel. The maximum power output increases by up to 38% and enhancement of the overall performance is more pronounced at lower flow rate region.

• Proceedings of the KSME Conference
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• 2005.11a
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• pp.96.1-96.1
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• 2005

• Journal of IKEEE
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• v.18 no.1
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• pp.152-158
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• 2014

It is very important to supply the diesel fuel from fuel tank to combustion chamber in case of cold start procedure. the paraffin hydrocarbons are easily solidified at low fuel temperature and it can be blocking the fuel supply to the high pressure fuel pump. In order to reduce the fuel crystallization (Waxing), it have been used to develop not only cold flow additives but also the proper mounting design of fuel filter. Block heater in the fuel filter assembly have been also contained to improve the cold start and prevent blocking the fuel supply in Common Rail Direct Injection System. we can obtain the fuel pressure drop and fuel flow rate, power consumption of fuel heater to have the cold flow evaluation test with the saperated and composited fuel heater at the low ambient temperature, Due to evaluating cold flow performance of two block heater, we knew that composited package fuel heater was the excellent cold flow performance compared to separated type and obtained the parameters of cold flow.

• Journal of Hydrogen and New Energy
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• v.33 no.5
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• pp.550-556
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• 2022

In this study, the flow uniformity was analyzed by performing numerical analysis on the 1 kWe internal manifold type solid oxide fuel cell stack according to the channel height of the separator. Also, it was examined by varying the fuel utilization rate and oxygen utilization rate. From the calculation results, we found that as the channel height of the separator decreased, the pressure drop increased exponentially. In addition, it was found that as the channel height of the separator decreased, the gas flow resistance inside the unit cell increased, and the flow resistance increased the pressure drop, thereby improving the flow uniformity inside the stack. Finally, the calculation results showed that as the fuel and oxygen utilization increased, the flow uniformity also improved.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.58 no.4
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• pp.563-567
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• 2009

The polymer electrolyte membrane fuel cell(PEMFC) with the advantages of low-operating temperature, high current density, low cost and volume, fast start-up ability, and suitability for discontinuous operation becomes the most reasonable and attractive power system for transportation vehicle and micro-grid power plant in a household. 200W PEM-type FCs system was integrated by this study, then the electrical characteristics and diagnosis of the fuel cell were analyzed with variations on mass flow rate and stack temperature. The ranges of the variations are 1~8L/min on $H_2$ volume and $20{\sim}70^{\circ}C$ on stack temperature.

• 한국연소학회:학술대회논문집
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• 2000.05a
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• pp.35-44
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• 2000

It was numerically studied that NOx emission characteristics of confined $CH_{4}$ jet flames with the variation of the diameter of inner fuel nozzle, the flow rate of $CH_{4}$ and equivalence ratio. Parabolic type equations were adopted in the calculation and GRI-2.1I mechanism was used for the chemical reaction. NOx emission index (EINOx) was introduced to evaluate NOx emission quantitatively in parametrically varied flames and the contribution of Thermal and Prompt NO mechanism was discussed. The results showed that Total EINOx varied sensitively with the variation of the flow rate of$CH_{4}$ but it was not sensitive to the variation of the diameter of inner fuel nozzle. Thermal EINOx showed the similar tendency to total EINOx and Prompt EINOx showed insensitivity to the variation of the diameter of inner fuel nozzle and the flow rate of $CH_{4}$.

• Journal of Hydrogen and New Energy
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• v.22 no.2
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• pp.191-198
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• 2011

According to the propagation of fuel cell system, the importance of that system efficiency is being magnified. Thus, the efficiency improvement of reformer which is the important factor of fuel cell system will be required. This study has been experimentally performed to evaluated the performance of plate type STR reactor. At first, we changed fuel flow rate (2, 3 and 4 l/min) in burner, and then we measured a proportion of hydrogen in produced gas through the STR reactor by G.C for evaluating the performance of plate type STR reactor in various fuel supply conditions. And we changed S/C ratio (2 and 4) and measured a proportion of hydrogen in produced gas through the STR reactor. As a results, condition at fuel flow rate 2 and 3 l/min could not be supplied amount of heat for STR sufficiently. Condition at fuel flow rate 4 l/min could supplied a heat excessively. And condition at S/C ratio 2, reaction occurred insufficiency. But condition at S/C ratio 4 was excess. From above, we found the optimum conditions that were fuel rate 3.5 l/min and S/C ratio 3.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2011.11a
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• pp.293-298
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• 2011

The combustion and flow-rate control characteristics of fuel-rich gas generator which could be adopted to Ducted Rocket propulsion system are investigated. The gas generator is designed considering the design requirements of propulsion system and solid fuel for fuel-rich combustion is developed then adopted to ground test. The results of combustion test show the necessity of the special analysis tool for estimating the gas generator performance where multi-phase flow of fuel-rich gas exists. During the flow-rate control test, characteristics of gas generator pressure with the angle of valve are analyzed and, method to estimate the pressure of gas generator is suggested using the relation between the valve exit area and discharge coefficient.

• Journal of the Korean Society of Combustion
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• v.9 no.3
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• pp.1-9
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• 2004

This study is aimed to characterize the combustion behavior of solid fuel in the various types of the combustors: stoker, rotary kiln and fluidized bed type combustors. Three different types of reduced-scale combustors are introduced, and temperatures and flue gas compositions are measured for various fuel sizes, water contents, initial temperature, and air flow rates. In case of the rotary kiln combustor, effects of rotating speed of the combustor are also investigated. Mean carbon conversion time (MCCT) and flame propagation rate (FPR) are used for the quantitative analysis. It is revealed that the reaction rates of the fuel are significantly influenced by the fuel characteristics, type of the combustors and air flow rate. Major design parameters for each type of the combustors are summarized through the reduced-scaled model analysis.

• 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.