권호 표지

Korean Journal of Air-Conditioning and Refrigeration Engineering (설비공학논문집)

The Society of Air-Conditioning and Refrigerating Engineers of Korea

  • Monthly
  • /
  • 1229-6422(pISSN)
  • /
  • 2465-7611(eISSN)

Domain

  • Construction/Transportation ＞ Construction Engineering/Materials/Management
  • Construction/Transportation ＞ Construction Environment/Equipment

Aim & Scope

The Korean Journal of Air-conditioning and Refrigeration Engineering (KJACR) is a journal publishing articles with essential reading for all those in the entire Asia wishing to keep abreast of research and industrial technologies in air conditioning, refrigeration, building physics and systems. The aim is to present new research results, and new proven practice aimed at minimizing energy demands of building and improving indoor air quality. Articles reporting practical and experimental researches focusing on heating, cooling, ventilation, indoor environments of buildings, sanitation and plant facilities are welcome. In addition, it covers future energy technologies such as new & renewable energy, waste heat energy, and etc. Especially, the journal welcomes papers on HVAC and building technologies in various climatic conditions, such as Asian countries. KJACR was registered to the National Research Foundation of Korea and part of the articles are abstracted in Korean Citation Index(KCI). Full text is available from http://www.sarek.or.kr and there is no page charge or article processing charge of author side. Topics covered include: Heating, ventilation and air-conditioning (HVAC) Refrigeration Building systems Building physics Energy saving and energy efficiency Renewable and sustainable energy Mass and heat transfer Indoor air quality (IAQ) Thermal comfort Simulation

http://www.sarek.or.kr/ KSCI KCI

Volume 28 Issue 8

  1. Lee, Donggyu;Park, Sechang;Chung, Dong-yeol;Kang, Cheadong 305
    https://doi.org/10.6110/KJACR.2016.28.8.305 PDF KSCI
    A thermal storage systems was designed to correspond to the temporal or quantitative variation in the thermal energy demand, and most of its heat is stored using the latent and sensible heat of the heat storage material. The heat storage method using latent heat has a very complex phenomenon for heat transfer and thermal behavior because it is accompanied by a phase change in the course of heating/cooling of the heat storage material. Therefore, many studies have been conducted to produce an experimentally accessible as well as numerical approach to confirm the heat transfer and thermal behavior of phase change materials. The purpose of this study was to investigate the problems encountered during the actual heat transfer from an internal storage tank through simulation of the process of storing and utilizing thermal energy from the thermal storage tank containing charged PCM. This study used analysis methods to investigate the heat transfer characteristics of the PCM with simultaneous heating/cooling conditions in the rectangular space simulating the thermal storage tank. A numerical analysis was carried out in a state considering natural convection using the ANSYS FLUENT(R) program. The result indicates that the slope of the liquid-solid interface in the analysis field changed according to the temperature difference between the heating surface and cooling surface.
  2. Jeong, Sung-Chol;Yun, Rin 311
    https://doi.org/10.6110/KJACR.2016.28.8.311 PDF KSCI
    The efficiency of manure treatment was investigated in terms of the pH, BOD, COD, SS, T-N and TP with a variation in the injection amount of PAC, polymer and ozone. The wastewater flow rate to the AOF is of $7.4m^3/hr$ with a reaction time of 30 minutes. The amount of PAC and polymer changed by 30, 35, 40 ml/min, and 30, 40, 50 ml/min, respectively. The amount of ozone injected varied from 110, 125, and $150kg-O_3/hr$. The optimum manure treatment performance was found for a PAC of 35 ml/min for the COD and SS, with polymer of 30 ml/min, and ozone injection of $150kg-O^3/hr$. A substantially optimum dose for each PAC, polymer, and ozone was also found to exist.
  3. Park, Min-Hee;Moon, Seung-Jae;Lee, Dae-Young 316
    https://doi.org/10.6110/KJACR.2016.28.8.316 PDF KSCI
    This study investigated a compact regenerative evaporative cooler (REC). To achieve practical applications of an REC, it is very important to consider the compactness as well as the cooling performance. Therefore, a prototype of the REC was designed and fabricated to improve the compactness by reducing the length through the insertion of fins in both the dry and wet channels. The REC prototype was tested in terms of performance evaluation under various operating conditions. An analytical model was also developed to analyze the effects of the axial conduction through the solid body of the REC, the wetness of the surface in the wet channel, and the thermal capacity of the evaporation water flow. The model was validated by comparing the results of a simulation with experimental data. The numerical simulation was based on the model to analyze the performance of the REC and to suggest methods to improve the cooling performance of the REC. Finally, the performance of the present REC was compared to that obtained in previous experimental studies. The results showed that the REC prototype in the present study is the most compact and achieves the highest cooling performance.
  4. Jeon, Byungyong;Ko, Wonbin;Park, Youn Cheol 325
    https://doi.org/10.6110/KJACR.2016.28.8.325 PDF KSCI
    This study was conducted to develop a heating system for a fuel cell-driven electric vehicle. The system consists of a compressor, an expansion device and three heat exchangers. A conventional air source heat exchanger is used as primary heat exchanger of the system, and an additional water source heat exchanger is used as a pre-heater to supply heat to the upstream air of the primary heat exchanger. On the other hand, the third heat exchanger consists of a water-to-refrigerant heat exchanger. The heat source of the pre-heater and the water-refrigerant heat exchanger is the waste heat from the fuel cell's stack. In the experiment, the indoor and the outdoor air temperature were fixed, and the compressor speed, EEV opening and waste heat temperature were varied. The results indicate that the $COP_h$ of the proposed system is 3.01 when the system is operating at a 1,200 rpm compressor speed, 50% EEV opening, and $50^{\circ}C$ waste heat source temperature in air pre-heater operation. However, when the system uses a water-refrigerant heat exchanger, the $COP_h$ increases to up to 9.42 at the same compressor speed and waste heat source temperature with 75% EEV openings.
  5. Lee, Dae-Woong;Lee, Eun-Woung 331
    https://doi.org/10.6110/KJACR.2016.28.8.331 PDF KSCI
    This study presents a coolant density calculation device and its corresponding method by using a mass flowmeter and the LabVIEW program. The method can be easily measured with a mixture of coolant and by calculating the percentage of ethylene-glycol without additional investment. The cooling water is very important in a vehicle to protect the engine, and the cooling performance is affected by the mixture concentration and coolant density. The coolant density calculation device measures the mixed concentration in the anti-freeze cooling mixture made from distilled water and ethylene-glycol in real time with the mass flowmeter that is commonly attached to the radiator or heater core. The calculation program for the mixture concentration percentage was developed using the LabVIEW software. The correlation between experimental results and the calculation was conducted for a range of temperature from 40 to $90^{\circ}C$ and by varying the mixture ratio of distilled water and ethylene-glycol. As a result, the anti-freeze coolant concentration in the volume percentage is able to monitor the coolant density in a timely basis by implementing a mixture concentration calculation program without the need for additional equipment investment. The results of the calculation for the mixture concentration level show a maximum 2.7% deviation compared to the experimental results.
  6. Seong, Hongseok;Lee, Chungho;Suh, Jeongse 337
    https://doi.org/10.6110/KJACR.2016.28.8.337 PDF KSCI
    A marine SCR System is emerging as an alternative to comply with NOx Tier III Emission standards, a restriction on greenhouse gas from vessels implemented by the International Maritime Organization. The system is greatly affected by the uniformity of the fluid flowing into the catalyst, so the performance of the catalyst of an SCR system needs to be guaranteed. This study conducted research on a mixed evaporator of an SCR system, which is one of the factors affecting the uniformity of the fluid. When the angle of the mixed evaporator is set to $90^{\circ}$, the fluid uniformity is at its highest at 83%, under the condition that the length of the mixed evaporator be 3.5 D. When the length was 3.5 D and less, the fluid uniformity had a tendency to improve relative to the case without a bent pipe. However, a longer mixed evaporator results in a more perfect liquidity development in the pipe with a liquidity distribution similar to the case where no curved pipe is formed in front of the catalyst. A lower angle for the mixed evaporator results in a lower flow uniformity, and a longer length of the mixed evaporator results in a lower difference in the flow uniformity caused by the angle. The flow uniformity can be improved by 6% with a mixed evaporator, which confirmed that all factors applied to an SCR system have a close relationship with the efficiency.