• Journal of Drive and Control
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• v.16 no.2
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• pp.51-58
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• 2019

In this study, flow analysis and dehumidification experiment were conducted on hollow fiber membrane module to determine the dehumidification characteristics of its various configurations. A quantitative analysis of the CFD for four different models with a temperature of $30^{\circ}C$ and 30%RH inlet humidity was conducted. Each model has different shape parameters i.e. the number of hollow fiber membranes and the presence or absence of baffles. After comparison between the flow analysis results and dehumidification experiment results, the percentage error was found to be approximately 2%. The moisture removal rate for each model was calculated using flow analysis data. It was found that the moisture removal rate of refined model with three baffles and eight hollow fiber membranes was highest among the four modeled modules of hollow fiber membrane one, i.e. about 60%.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.28 no.5
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• pp.594-603
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• 2004

Several desiccant cooling systems have been developed in terms of cost and performance. In this study a fin-tube exchanger has been used for liquid desiccant dehumidification system. This dehumidifier has been designed to study the absorption characteristic of the aqueous triethylene glycol(TEG) solution which has the flow range from 20 to 50 LPM. The dehumidifier performance characteristics of working factor variables such as inlet solution flow rate, air flow rate, solution concentration and brine temperature have been analyzed. This dehumidifier has the ability to provide running while saving the latent heat load of total energy. The result of this experiment can provide useful data for hybrid air conditioning system.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.7
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• pp.845-852
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• 2003

Liquid desiccant dehumidification system can be used effectively to save energy consumed in air conditioning as an alternative compared with conventional air conditioning systems by reducing latent heat load. The dehumidifier and the regenerator from the heart of this system. The latent part of the cooling load is handled using liquid desiccant. In this study, the experimental regenerator has been designed to study the regeneration characteristics of the aqueous triethylene glycol(TEG) system. The performance factors of the regenerator with finned tube heat exchanger were evaluated by a series of experimental runs. The regeneration process is highly dependent on the liquid desiccant conditions, such as, temperature, concentration and flow rate. In addition, the effects of the inlet air temperature, humidity and flow rate were discussed. Data obtained are useful for design guidance and performance analysis of a regenerator, particularly for a liquid desiccant cooling system.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.27 no.12
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• pp.620-625
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• 2015

The summer climate is very hot and humid in Korea. Humidity is an important factor in determining thermal comfort. Recently, research on dehumidification device development has been attempted to save the energy required for operating the dehumidifier. Existing dehumidification systems have disadvantages such as wasting energy to drive the compressor. Meanwhile, dehumidification systems with membranes can dehumidify humid air without increasing the dry bulb temperature. Therefore. they don't have to consume cooling energy. In this paper, the installation conditions for a membrane system were analyzed to improve the shape and optimum performance of the system. The results showed that the distance between elements was the critical system design factor, and that a distance of 20 mm was the optimal condition for the pressure drop and flow characteristics of the internal air flow.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.7
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• pp.630-638
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• 2004

Liquid desiccant dehumidification systems have the ability to provide efficient humidity and temperature control while saving the electrical energy requirement for air conditioning as compared to a conventional system. The dehumidifier and the regenerator form the heart of this system. The latent part of the cooling load is overcome using liquid desiccant. The model regenerator has been designed to study the absorption characteristic of the aqueous triethylene glycol (TEG) solution which is in the flow range from 20 to 50 LPM. Also, this system designed that was able to change the height of the regenerator and dehumidifier. Because the effect of performance have different result according the height. The effect of performance factors of the regenerator with inlet solution flow rate, air flow rate, solution concentration, solution temperature, brine temperature, air temperature and inlet air relative humidity have been analyzed. Data obtained are useful for design guidance and performance analysis of the hybrid air conditioning system.

• International Journal of Aeronautical and Space Sciences
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• v.3 no.1
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• pp.9-18
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• 2002

Thermal humidity characteristics were considered theoretically and experimentally. A Simply well-fitted correlation of a saturated vapor pressure-temperature curve of water was introduced based on Antoine equation to make theoretical prediction of relative humidity according to temperature variation. Characteristics of dew point were also examined theoretically and its relation with temperature and humidity was evaluated. The exact mass of water vapor in a specified humidity and temperature condition was estimated to provide useful insight into the idea about how much amount of water corresponds to a specified humidity and temperature condition in a confined system. A simple but well-fitting model of dehumidification process was introduced to anticipate the trend of relative humidity level during GN2(gaseous nitrogen) purge process in a humidity chamber. Well-suitedness of this model was also verified by comparison with experimental data. The overall appearance and specification of two thermal humidity chambers were introduced which were used to perform various thermal humidity tests in order to yield useful data necessary to support validity of theoretical models.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.158-163
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• 2001

Performance of the water direct contact air conditioning system, in which heat and mass are transferred directly between air and water droplet, is simulated by semi-empirical method. This system improves transport efficiency compared to conventional indirect contact system and cooling, heating, dehumidification and humidification are attained with one unit. In this study, temperature and flowrate for air and water are measured in the various cooling and heating conditions, and correlations for $h_{c}A/c_{pm}$ are derived from these data. Cooling and heating characteristics of the water direct contact air conditioning system are investigated using correlations.

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.119.1-119
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• 2002

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.24 no.1
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• pp.16-22
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• 2012

Experimental investigations were carried out to examine the heat and mass transfer characteristics of LiCl aqueous solution for a plate heat exchanger type dehumidifier. Cooling dehumidification was adopted vertical type heat exchanger. Also non woven fabric is attached surface of the heat exchanger for spreadability of LiCl aqueous solution. Mass flow-rate of LiCl aqueous solution and concentration were selected as experimental conditions. Also, In this study, the effects of relative humidity of process air and velocity were investigated experimentally. As a result of heat transfer coefficient and mass transfer coefficient of were increased film reynolds number increased. heat transfer coefficient and mass transfer coefficient of LiCl aqueous solution were 0.14~0.24 kW/$m2^{\circ}C$ and $1.3{\times}10-63{\sim}6.2{\times}10-6$ m/s respectively.

• Proceedings of the SAREK Conference
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• 2005.11a
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• pp.359-364
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• 2005

In dehumidification evaporation cooling system. the regeneratie evaporative cooler(REC) makes an important role to reduce the sensible cooling load in the system through evaporative cooling, By this reason, many studies about increasing the cooling capacity of the REC were undertook. In this paper, we analyzed the cooling characteristics of the REC due to the structures of the REC and determined the best structure for the REC's effectiveness and cooling capacity. From the study. we could obtain some important results: at first. corrugated type has the benefit to expand the channel width of the REC, But because the type has some weak points about the size and weight. there is almost no benefit to improve the performance of the REC. Through these reasons. we decided that finned type is the best structure to improve the performance of the REC.