• 한국기계가공학회지
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• 제14권5호
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• pp.42-49
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• 2015

In this study, the multi-disk of a high-pressure drop control valve is designed and manufactured. Then, the flow rate and high-pressure drop of fluids flowing in the high-pressure drop control valve is CAE/CFD. This study involves numerical analysis for the Zambil offshore project of a high-pressure drop control valve. ANSYS used a solver for offshore structures analysis. A high-pressure drop control valve, which transforms the power transfer of a system by reducing the inlet pressure of 345bar to the outlet pressure of 112bar, is a fundamental component in the offshore process. This study not only analyzes the relation between pressure drop and fluid velocity in a trim by using fluid analysis, but also examines the possibility of cavitation in a valve in addition to the plot for the extension of lifespan. It is demonstrated that the pressure drop from 345bar to 112bar is more feasible in the presence of the trim, which can induce a continuous and diminutive pressure drop in order to prevent cavitation in a high-pressure drop control valve.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
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• pp.172-177
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• 2005

The object of this experiment is comparing heat transfer performance and pressure drop characteristics by baffle cut rate, fluid velocity and heating temperature. Experiments were carried out in cross flow heat exchanger with water as a working fluid. In this experiment, baffle cut rate is 30%, 40%, 50%, velocity is 0.5m/s, 1.0m/s, 1.5m/s, and heating temperature is $30^{\circ}C$, $40^{\circ}C$, $50^{\circ}C$. An experimental device to measure the heat transfer coefficient was constructed. The experimental result were obtained for the fully developed turbulent flow of water in tube on the condition of uniform heat flux.

• 설비공학논문집
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• 제14권5호
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• pp.385-390
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• 2002

To clarify the hydraulic characteristics of ice slurry which made from 6.5% ethylene glycol-water solution flowing through circular pipes of small diameter, experimental studies were performed. The flow pattern was observed and the pressure drop was measured in acrylic pipes with inner diameter of 24 mm. The results of flow visualization revealed that ice particles flowed along the top of pipes in the ranges of small ice fraction and low flow rate, while Ice particles diffused into the whole region of pipes flowed like a homogeneous flow for high flow rate and high ice fraction. An increase in frictional pressure drop was measured as the ice fraction increased in all pipes and unstable flow was observed for up-ward vertical pipe.

• 한국소음진동공학회논문집
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• 제15권4호
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• pp.452-456
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• 2005

Cyclone is widely adopted in the vacuum cleaner, because of the simple structure, the high dust collection efficiency and its transparency feature, which can be shown to the customer. At past times, cyclone performance was represented by collection efficiency, flow rate, pressure drop etc. At recent times the noise problem is getting important as cyclone comes into home-appliances. In this paper, pressure drop of cyclone and it's noise were measured at the variation of the cyclone structure and the main sources of cyclone peak noise was found by experimental and numerical analysis. In addition, the structure for peak noise reduction was suggested and it is beneficial both pressure drop and noise reduction.

• 설비공학논문집
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• 제14권6호
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• pp.485-492
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• 2002

Heat transfer and pressure drop on the air side of a plate-louvered fin heat exchanger with new shape of louver fin have been investigated experimentally. Water is employed inside the flat tube to transfer heat with air for convenience. This problem is of particular interest in the design of a plate-louvered heat exchanger. The effect of air flow rate, water flow rate and water temperature on pressure drop as well as heat transfer in air side are studied in detail. The present results showed a good agreement qualitatively with the previous results in general. Based on the experimental data, f-factor and j -factor correlations of the present louvered-fin are suggested. It is also found that heat transfer could be enhanced with new shape of louver fin, compared with the conventional louvered-fin, while the f-factor remains unchanged.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.192-197
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• 2008

The objectives of this paper are to measure the heat transfer and pressure drop of the heat transfer tube for an evaporator of absorption system applications. Five types of heat transfer tubes with different shape and heat transfer area are tested in the present experiment. Heat transfer and pressure drop performance of heat transfer tubes are measured in various operating conditions, and compared each other. The results show that the heat transfer rate of thermoexcel notch tube and low fin tube increases about 27.6% and 11.6% at the refrigerant flow rate 250 kg/h compared with that of bare tube, respectively. The thermoexcel notch tube is shown the best performance considering pressure drop and heat transfer coefficient.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2004년도 추계학술대회논문집
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• pp.89-92
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• 2004

Cyclone is widely apoted in the vacuum cleaner, because of it's simple structure, the dust collection efficiency is high and its transparency feaure which can be shown to the customer. At past times, cyclone performance is represented by collection efficiency, flow rate, pressure drop etc. At recent times the noise problem is getting important as cyclone comes into home-appliances. In this paper, cyclone's pressure drop and noise is measured at the variation of the cyclone structure and the main sources of cyclone peak noise is found by experiments and numerical analysis. In addition, the structure for peak noise reduction is suggested and it is beneficial both pressure drop and noise reduction.

• 한국수소및신에너지학회논문집
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• 제15권3호
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• pp.194-200
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• 2004

Thermal energy performance of a brazed plate heat exchanger has been evaluated experimentally. The effects of plate pitch as well as chevron angle of a plate heat exchanger on the heat transfer rate and pressure drop have been investigated in the wide range as mass flow rates in detail. This problem is of particular interest in the design of a plate heat exchanger. The results obtained indicate that both heat transfer rate and pressure drop are increased as mass flow rate is increased, as expected. It is also found that the heat transfer rate is increased with a decrease in the plate pitch while the heat transfer is decreased with a decrease in the chevron angle. Friction factor correlations are suggested based on the measured pressure drop and effectiveness of plate heat exchangers are also compared.

• International Journal of Air-Conditioning and Refrigeration
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• 제16권4호
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• pp.117-123
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• 2008

The present study is directed at flow and heat transfer of $CO_2$ and oil mixtures in a circular tube. PAG and POE oils are considered in this study. Flow characteristics of $CO_2$ and oil mixtures have been investigated by flow visualization. Pressure drop has been measured in the range of operating mass flow rate from 0.1 to 0.4 kg/min in a circular tube. Heat transfer characteristics of $CO_2$/oil mixtures have been investigated using a counterflow heat exchanger. In case of pure liquid $CO_2$ as well as $CO_2$ and POE mixtures, flow are seen to be uniform so that $CO_2$ and POE oil are still miscible even at flowing state. However, it is found that $CO_2$ and PAG are not miscible. Pressure drop of $CO_2$/PAG mixtures are much higher than that of $CO_2$/POE mixtures as well as pure $CO_2$ at a fixed mass flow rate. As the concentration of POE oil is increased from 0 to 5 wt%, pressure drop is increased. However, heat transfer rate and heat transfer coefficient of $CO_2$/POE mixtures are much higher than that of $CO_2$/PAG mixtures. The f-factor correlation and Nusselt number correlation for $CO_2$/POE oil mixtures are suggested in this paper.

• 한국자동차공학회논문집
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• 제21권6호
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• pp.72-80
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• 2013

For the proper cooling of in-wheel motor, the cooling channel should have the characteristics which are low pressure drop and adequate cooling oil supply to motor part. In this study, the flow performance of cooling channel for in-wheel motor was evaluated and the shape of the channel was optimized. First, the pressure drop and flow distribution characteristics of the initial channel model were evaluated using numerical analysis. Also, by the result of analysis and design modification, 4 design parameters of the channel were selected. Second, using the Taguchi optimal method, the cooling channel was optimized. In the method, nine models with different levels of the design parameters were generated and the flow characteristics of each models was estimated. Base on the result, the main effect of the design parameters was founded and optimized model was obtained. For the optimized model, the pressure drop and oil flow rate were about 0.196 bar and 0.207 L/min, respectively. The pressure drop decreased by about 0.3 bar and the oil flow rate to the motor part increased by about 0.2 L/min compared to the initial model.