• Title/Summary/Keyword: Conditioning

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Study on Non-uniform Thermal Comfort in Hybrid Air-Conditioning System with CFD Analysis (CFD 해석을 통한 하이브리드 공조시스템의 인체 온열감의 불균일성에 관한 연구)

  • Nam, Yu-Jin;Sung, Min-Ki;Song, Doo-Sam
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.23 no.3
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    • pp.216-222
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    • 2011
  • Recently, hybrid air-conditioning system has been proposed and applied to achieve building energy saving. One example is a system combining radiation panel with natural wind-induced cross-ventilation. However, few research works have been conducted on the non-uniformity of thermal comfort in such hybrid air-conditioning system. In this paper, both thermal environment and non-uniform thermal comfort of human thermal model under various air-conditioning system, including hybrid system, were evaluated in a typical office room using coupled simulation of computation fluid dynamics, radiation model and a human thermal model. The non-uniformity of thermal comfort was evaluated from the deviation of surface temperature of human thermal model. Flow fields and temperature distribution in each case were represented.

A System Operating Algorithm for the Effective Operation of a Multi-type Air-conditioning System (멀티형공조시스템의 효과적인 운전을 위한 시스템운전알고리즘)

  • Han Do-Young;Park Kwan-Jun
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.18 no.7
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    • pp.587-595
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    • 2006
  • A system operating algorithm was developed for the effective operation of a multi-type air-conditioning system. The system operating algorithm includes control algorithms for a safety mode, an initial operating mode, a stabilization mode, a fault diagnosis mode, an efficiency mode, and a tracking mode. Various tests were performed to show the effectiveness of these algorithms. Tests showed good results for the operation of a multi-type air-conditioning system. Therefore, these algorithms developed for this study may be used for the effective control of a multi-type air-conditioning system.

The Optimal Control of an Absorption Air Conditioning System by Using the Steepest Descent Method

  • Han Doyoung;Kim Jin
    • International Journal of Air-Conditioning and Refrigeration
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    • v.12 no.3
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    • pp.123-130
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    • 2004
  • Control algorithms for an absorption air conditioning system may be developed by using dynamic models of the system. The simplified effective dynamic models, which can predict the dynamic behaviors of the system, may help to develop effective control algorithms for the system. In this study, control algorithms for an absorption air conditioning system were developed by using a dynamic simulation program. A cooling water inlet temperature control algorithm, a chilled water outlet temperature control algorithm, and a supply air temperature control algorithm, were developed and analyzed. The steepest descent method was used as an optimal algorithm. Simulation results showed energy savings and the effective controls of an absorption air conditioning system.

The Experimental Study on Thermal Characteristics of PEM(Personal Environment Module) System (개별환경제어(PEM)시스템의 열적 특성 및 성능개선에 관한 연구)

  • 조성환;장철용;태춘섭
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.12 no.5
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    • pp.439-447
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    • 2000
  • The PEM(Personal Environment Module) system is an individual air conditioning system developed in order to improve thermal comfort in office buildings. In this study, thermal characteristics of a PEM system have measured experimentally and compared with UFAC(Under Floor hir Conditioning) system in the EC(Environment Chamber) constructed in KIER. Results showed that the PEM system was better than UFAC system for thermal comfort and energy conservation.

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An Economic Analysis of the Natural Gas Air-conditioning (가스냉방의 경제성 분석)

  • Gim, Bong-Jin;Park, Yearn-Hong
    • IE interfaces
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    • v.11 no.1
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    • pp.207-214
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    • 1998
  • Since the natural gas air-conditioning not only increases the base load of the gas company but also decreases the summer peak load of the electricity company, it is considerded as an efficient demand-side management program. This paper suggests the economic evaluation method of the gas air-conditioning program from the perspectives of the participants, the pipeline gas company, the local distribution company, the electricity company, and the total resources. The absorption type gas air-conditioning/space-heating is selected as a case study to illustrate the economic analysis of the natural gas air-conditioning.

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Study on the Reasonable Use and Effective Distribution of Diverse Air Conditioning Systems (냉방시스템 보급 활성화를 위한 방안 연구)

  • Kim, Min-Soo;Kim, Yong-Chan;Jeong, Si-Young
    • Proceedings of the SAREK Conference
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    • 2008.06a
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    • pp.208-213
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    • 2008
  • In this study, the policies to support reasonable use and effective distribution of air conditioning systems of ice storage type and natural gas type have been investigated. First, this study focused the current policy to stimulate the distribution of these air conditioning systems. Second, the advantage and disadvantage for the air conditioning systems of each type were evaluated. Finally, several policies are proposed for nationwide rational use of energy resources.

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