Transactions of the Society of Heating,Air-conditioning and Sanitary Engineers of Japan
Online ISSN : 2424-0486
Print ISSN : 0385-275X
ISSN-L : 0385-275X
Volume 45, Issue 281
Displaying 1-6 of 6 articles from this issue
Scientific Paper
  • Part 2-Evaluation of Degradation and Estimation of Lifetime
    Kazumi NAKAYAMA, Takayuki SAITO, Tomoko WATANABE, Yoshito OHTAKE
    2020 Volume 45 Issue 281 Pages 1-7
    Published: August 05, 2020
    Released on J-STAGE: August 05, 2021
    JOURNAL FREE ACCESS

    A degradation analysis was performed for thermally degraded nonflammable corrugated fiberboard ducts to estimate its lifetime. The material that was most likely to degrade and lead to the deterioration of duct performance was searched. This was because, even though the ducts are composed of many types of material, their performance decrease with the performance deterioration of only one material. It was found that the degradation of the pressure sensitive adhesive of the aluminum glass cloth tapes, which is a constituent of the nonflammable corrugated fiberboard ducts, has the greatest influence on the duct performance. A lifetime estimation model was constructed based on the results of the degradation analysis of the adhesive. The model showed that the lifetime of the nonflammable corrugated fiberboard ducts was estimated to be over 30 years, under 313 K. Thus, it is concluded that the nonflammable corrugated fiberboard ducts have sufficient long-term durability for application in air conditioning systems. 

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  • Part 1-Experimental Results of Small Equipment and Calculation Model of Adsorption Thermal Storage Tank
    Haruyuki KAMATA, Yoshiaki KAWAKAMI, Takamasa OYAMA, Satoru MATSUDA, Ma ...
    2020 Volume 45 Issue 281 Pages 9-17
    Published: August 05, 2020
    Released on J-STAGE: August 05, 2021
    JOURNAL FREE ACCESS

    We developed the open-cycle type adsorption thermal storage system with high density heat storage and no heat loss (no heat storage loss) related to the temperature with the outside air. Based on adsorbent of the HAS-Clay that have been developed by the National Institute of Advanced Industrial Science and Technology (AIST), this thermal storage system can utilize the low-temperature waste heat. Characteristics of charging and discharging operation were studied experimentally about the packed bed of HAS-Clay. In this paper, first, the features of adsorption thermal storage technology and the developed thermal storage material (Granulated HAS-Clay) are described. Second, the characteristics of charging and discharging operation is introduced by the experimental data. Last, the simulation model of adsorption thermal storage tank is explained though the comparison of calculation result and experimental result on the charging and discharging operations.

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  • Part 1-Numerical Evaluation of Contaminant Capture Efficiency of Fume Hood under Inappropriate Low Exhaust Airflow Rate
    Ryota MUTA, Sung-Jun YOO, Kazuhide ITO
    2020 Volume 45 Issue 281 Pages 19-26
    Published: August 05, 2020
    Released on J-STAGE: August 05, 2021
    JOURNAL FREE ACCESS

    A fume hood is a type of local ventilation device that is designed to limit exposure to hazardous or toxic fumes, and it is sometimes called a draft chamber (especially, in Japan) or a fume closet. Its most important objective is to protect the user from inhaling toxic gases generated in the closet. The performance of a fume hood in terms of protection from hazardous gases generally determined in each country. The average surface wind speed at the apertural area with the sash is required to be 0.5m/s or more. However, this performance evaluation conditions, and criteria is carried out under ideal environmental conditions and there are few examples of precise measurement/prediction of inhalation exposure risk to users under actual environment conditions. In this study, we numerically investigate the protection performance of a fume hood under realistic environmental conditions. For this, the precise fume food model installed in the general laboratory environment is reproduced for computational fluid dynamics (CFD) analysis. A computer simulated person (CSP) has the details of the human body shape, and the respiratory tract is also adopted for investigating inhalation exposure risk quantitatively. Integrated CFD-CSP simulations are conducted considering the frontal opening area, e.g., the apertural area with sash; and indoor environmental laboratory conditions, e.g., operating conditions of heating, ventilating, and air conditioning system. It was confirmed that the presence of a user in front of a fume hood and the operation of a room ventilation system has a significant effect on the surface wind speed distributions. 

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Technical Paper
  • Hiroyuki SHIRAIWA
    2020 Volume 45 Issue 281 Pages 27-34
    Published: August 05, 2020
    Released on J-STAGE: August 05, 2021
    JOURNAL FREE ACCESS

    Reducing the running cost of a cooling system of a data center can significantly reduce power consumption and CO<sub>2</sub> emissions. In this study, we conducted an experiment in a simulation facility for a new cooling system for data centers that was jointly devised with a joint research company that is a refrigeration and air conditioning equipment manufacturer and that actively utilizes low-temperature outside air conditions in winter and periods between seasons. We clarified the relationship between the outdoor wet-bulb temperature and room temperature. When the average wind speed of the heater fan was 3.2 m/s or higher and the outdoor wet-bulb temperature was 15 ℃ or lower, the room temperature could be maintained at 30 ℃ or lower. It has been proved that free cooling can be performed only with an evaporative condenser that does not allow the vapor compression refrigerator to function. 

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  • Part 1-Characteristics Model during Cooling Period
    Toshiyuki MIYANAGA, Tsuyoshi UENO, Ayako YASUOKA, Hiroyuki KITAHARA
    2020 Volume 45 Issue 281 Pages 35-43
    Published: August 05, 2020
    Released on J-STAGE: August 05, 2021
    JOURNAL FREE ACCESS

    Electric heat pump type multiple packaged air conditioning systems are a typical individual air conditioning system for commercial buildings. To increase user satisfaction and promote dissemination, it is important to be able to appropriately evaluate energy saving, comfort, and economy. Therefore, in this study, we improved the heat source characteristic model of the room air conditioner that we previously developed [Ueno, Kitahara, Miyanaga, Transactions of SHASE Japan, No.190(2013) pp.41-49)] and constructed a heat source characteristic model of a multiple packaged air conditioning system. In addition, the accuracy of the model was verified experimentally. Specifically, we conducted 150 cooling experiments of the multiple packaged air conditioning system to understand its operating characteristics, such as power consumption and COP of equipment. The experimental results were compared with model estimates. Since the measured values and the estimated values generally agreed well, the validity of this model was confirmed. As a result, the power consumption, COP, etc., of the multiple packaged air conditioning system during any steady cooling operation can be easily estimated. The greatest feature of this model is that a specific equipment model can be modeled using only data published by the manufacturer, making highly versatile.

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  • Part 5-Damage and restoration of equipment in the AMF from the Great East Japan Earthquake
    Hisashi WAKAYAMA, Nobutaka SATO, Yoshitaka ABE, Akira KOMODA
    2020 Volume 45 Issue 281 Pages 45-50
    Published: August 05, 2020
    Released on J-STAGE: August 05, 2021
    JOURNAL FREE ACCESS

    The Great East Japan Earthquake (GEJE) caused a tsunami and subsidence to Aquamarine Fukushima (AMF). Consequently, AMF suffered great damage. Outdoor heat source equipment, pumps for water treatment, and air conditioning machines in the B1 floor machine room were submerged by the tsunami. The first step to reopen AMF was to restore half the capacity of the aquarium equipment and building facilities. For example, only three of six pumps were available for the largest exhibit, the Sea of Kuroshio. This paper presents an outline of AMF aquarium equipment and building facility damage from the GEJE and the process of the recovery. One of the major purposes of this paper is to disclose the actual situation of AMF damage caused by the GEJE and the recovery process, and to use these experiences to make a model for business continuity planning in aquarium facilities. 

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