• 제목/요약/키워드: Refrigerating efficiency

검색결과 667건 처리시간 0.022초

전기 집진기에서의 Submicron 입자의 집진 특성에 관한 연구-II. 집진 효율 특성 (A Study on the Collection Characteristics of Submicron Particles in an Electrostatic Precipitator - II. Collection Efficiency Characteristics)

  • 김용진;여석준;유주식
    • 설비공학논문집
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    • 제13권7호
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    • pp.579-587
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    • 2001
  • This study investigates particle collection characteristics of a cylindrical electrostatic precipitator. Experimental work has been made for the submicron particles. The effects of polarity of discharge electrode wire, particle diameter, gas velocity, gas temperature, and specific corona power on the particle collection efficiency are investigated. The efficiency of negative corona is higher than that of positive corona. as the particle diameter increases, the efficiency is decreased when the diameter is in the range of 0.02-0.6 micron, but is increased for the nanometer particles with diameter smaller than 0.02 micron. The efficiency is increased with increase of specific corona power. As the gas temperature increases, overall collection efficiency is increased for a negative corona, but is deceased for a positive corona.

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판형 휜을 갖는 열교환기의 휜효율에 관한 수치해석적 연구 (Numerical study for the fin efficiency of the heat exchanger having plate fins)

  • 강희찬
    • 설비공학논문집
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    • 제11권6호
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    • pp.903-911
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    • 1999
  • This study is discussed about the heat transfer coefficient and the fin efficiency of the heat exchanger having plate fins. A new definition for the fin efficiency of the heat exchanger is proposed. More than one hundred cases were tested numerically for the plate fins having uniform and non-uniform heat transfer coefficient. The previous models for the fin efficiency and the pure heat transfer coefficient were applicable to the heat exchanger only when the NTU is very small. It was found that the fin efficiency of the heat exchanger was nearly the same as the normalized fin temperature. The present model could estimate the pure heat transfer coefficient within a few percent in the present test range of 0<NTU<2.5.

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건물에너지 효율향상을 위한 최적화 툴의 개발 (Development of Optimization Program for the Building Energy Efficiency Improvement)

  • 한수곤;임병찬;허정호;권한솔
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2005년도 동계학술발표대회 논문집
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    • pp.223-228
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    • 2005
  • This study develops an optimization program to use optimum design of building HVAC system reducing building energy use and cost. Doe20pt developed is an interface program between DOE2 and GenOpt to perform the optimization procedure more easily. The optimum results can be used to estimate the economical efficiency concerning the building management.

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인버터 압축기의 저속과 고속운전범위가 계절성능에 미치는 영향 (The effect on the seasonal performance of an inverter compressor with higher and lower operating range)

  • 박윤철;하도용;민만기
    • 설비공학논문집
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    • 제10권2호
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    • pp.173-179
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    • 1998
  • An experimental study was conducted on the effect of compressor capacity control range of heat pump on the seasonal energy efficiency ratio with variation of the maximum and minimum compressor input frequencies. To obtain seasonal energy efficiency ratio, steady state test at the maximum, minimum and intermediate compressor speed and cyclic test at the minimum compressor speed should be conducted. Maximum input frequency was varied to 95Hz, 105Hz, and 115Hz, and the minimum input frequency was varied to 35Hz, 45Hz, and 55Hz. The seasonal energy efficiency ratio increased as the input frequency of the compressor decreased. The maximum input frequency had only slight effects on the SEER.

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가정용 스털링엔진 열병합발전시스템 운전특성에 관한 연구 (The Operation Characteristics of Domestic Stirling Engine Cogeneration System)

  • 최재준;박병식;정대헌
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2009년도 하계학술발표대회 논문집
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    • pp.309-314
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    • 2009
  • The unpredicted worldwide oil price makes the energy efficiency technology be more importance than any other period. The small cogeneration system is one of the most representative technology among the energy efficiency technologies, and the Stirling engine cogeneration system has been concerned and investigated due to the preferable characteristics - low toxic emission, low noise and vibration level, and the various form of fuel. A tiny, 1kW of electrical output, gas fueled Stirling engine cogeneration system was investigated. The electrical efficiency and thermal efficiency of the system were measured. The experiment was executed at an independent Stirling engine mode, independent secondary burner mode, and the combined mode. Part load characteristics of the Stirling engine cogeneration system were investigated also. With the efficiency characteristics, the $O_2$ and NOx emission characteristics were measured.

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건물에너지효율등급 평가도구와 상세해석프로그램의 비교 분석 (An Analysis of Comparison between the Evaluation Tool for Building Energy Efficiency Rating System and Detailed Analysis Programs)

  • 이재혁;유기형;조동우
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2009년도 하계학술발표대회 논문집
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    • pp.3-8
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    • 2009
  • Since 2001, the Building Energy Efficiency Rating and Certification System have been implemented in Korea. For rating the energy efficiency performance, the evaluation tool for Building Energy Efficiency Rating System has been used. In this study, the evaluation tool was compared with detailed analysis programs(Trnsys 16, ESP-r) through simulations of heating energy needs for apartment, and we checked the character of the evaluation tool.

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