통합 검색 | Korea Science

조진균;정차수;김병선
- 설비공학논문집
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- 제22권4호
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- pp.205-212
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- 2010
In a typical data center, large numbers of IT sever racks are arranged multiple rows. IT environments, in which extensive electronic hardware is air-cooled, cooling system inefficiencies result when heated exhaust air from equipment prematurely mixes with chilled coolant air before it is used for cooling. Mixing of chilled air before its use with heated exhaust air results in significant cooling inefficiencies in many systems. Over temperatures may not only harm expensive electronic equipment but also interrupt critical and revenue generating services. Cool shield is a cost effective aisle partition system to contain the air in cold aisles and hot aisles of an IT server room. This paper focuses on the use of performance metrics for analyzing aisle partition system in data centers.
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장영준;박영철;정광섭;한화택;이정재
- 설비공학논문집
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- 제14권4호
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- pp.278-284
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- 2002
The work presented here provides a control of the supply duct outlet air temperature in PEM (personal environment module) using fuzzy PID controller. In previous work, PID control systems were used, but the result shows that the outlet air temperature and electric heater regulating voltage were oscillated. Fuzzy PID control systems are designed to improve the system response obtained using PID control and implemented experimentally Also, PID controller and fuzzy controller without PID logic are provided to compare the result with that of the fuzzy PID controller. Data obtained shows that the fuzzy PID control system satisfies the design criteria and works proper1y in controlling the supply air temperature. Also it has bettor performance than the previous result obtained using PID control.
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정석권;김동규;금종수;박종일
- 대한설비공학회:학술대회논문집
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- 대한설비공학회 2008년도 하계학술발표대회 논문집
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- pp.480-483
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- 2008
The cold-air distribution system is expected as an efficient method to reduce energy consumption in the air-conditioning system. We introduced some control strategies for the system by summarizing some references in the view point of energy saving. Direct digital control is specially emphasized as an important control technique for the system. Some drawbacks which habe been conventionally mentioned to apply the cold-air distribution to real fields can be solved by using the technique. The control strategy which is introduced in here will be available to build control system for the air-conditioning based on the cold-air distribution for energy saving.
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최익순;정광섭;박영철;한화택;이정재
- 설비공학논문집
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- 제13권2호
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- pp.106-114
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- 2001
The office environment of the building has been significantly changed and the office automation(OA) for productivity improvement and efficiency has proceeded. According to thee trends, the concept of office environment was transferred from conventional \"working space\" to \"living space\" or \"creative space\". Thus, occupants in office building have demanded more comfortable and advanced task environment. The objective of this paper is to evaluate the indoor environment of working space with personal air conditioning system using the measurements of environmental comfort parameters and the questionnaire survey of occupants、 thermal sensation response to the environment.n response to the environment.
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김태섭;홍금식;손현철
- 제어로봇시스템학회:학술대회논문집
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- 제어로봇시스템학회 2000년도 제15차 학술회의논문집
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- pp.221-221
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- 2000
The heat exchange part in a modern multi-type air-conditioning system employs multiple-pass heat exchangers. The heat-transfer performance of an each pass in such an exchanger depends strongly on the length of the two-phase region and the mass flow of the refrigerant. The total length and diameters of the pipes, the exit conditions, and the arrangement of each pass as well as the geometrical shape of the distributor at the branching sections are considered to be major factors affecting the heat-transfer performance. The refrigerant commonly used in these systems is HCFC-22. The two objectives of this paper are to investigate the characteristics of the refrigerant flow rate and the superheat in the evaporator of a multi-type air-conditioning system for a single or simultaneous operating conditions and to control the superheat and the refrigerant flow rate of the evaporator.
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