• 제목/요약/키워드: Outdoor unit

검색결과 239건 처리시간 0.025초

에어콘 실외기용 축류송풍기의 비정상 유동장 특성 연구 (Unsteady Flow Characteristics of an Axial Flow Fan Installed in the Outdoor Unit of Air Conditioner)

  • 장춘만
    • 유체기계공업학회:학술대회논문집
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    • 유체기계공업학회 2005년도 연구개발 발표회 논문집
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    • pp.223-230
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    • 2005
  • The unsteady nature of vortex structures has been investigated by a large eddy simulation (LES) in an axial flow fan with a shroud covering only the rear region of its rotor tip. The simulation shows that the tip vortex plays a major role in the structure and unsteady behavior of the vortical flow in the fan. The movements of the vortex structures induce high-pressure fluctuations on the rotor blade and in the blade passage. Frequency characteristics of the fluctuating pressure on the rotor blade are analyzed using wavelet transform. The dominant frequency of the real-time pressure selected at the high pressure fluctuation region corresponds well to that of the fluctuating rotor torque and the experimental result of fan noise. It is mainly generated due to the unsteady behavior of the vortical flow, such as the tip vortex and the leading edge separation vortex.

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에어컨 실외기 소음원 해석시스템 구축 연구 (Research on Noise Analysis Systems for Outdoor Unit of Airconditioner)

  • 김동진;홍석윤;송지훈
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2013년도 춘계학술대회 논문집
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    • pp.795-795
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    • 2013
  • 본 논문에서는 에어컨 실외기의 내부 소음원에 의한 방사소음의 수준을 예측하기 위한 해석시스템을 구축하였다. 에어컨 실외기를 구성하는 여러 구성품을 내부 모델과 외부 모델로 구분하여 모델링하고, 주요한 소음원에 대한 최소한의 해석을 통하여 에어컨 실외기의 방사소음 수준을 예측하였다. 에어컨 실외기의 주요한 소음원 데이터를 실험을 통하여 계측하고, 이를 소음원 입력값으로 하는 진동해석 및 방사소음해석을 실시하여 구성품별 기여도를 예측 및 내부 구성품에 의한 소음원 데이터를 도출하였다. 해석을 통해 도출된 소음원 데이터를 이용하여 구조-음향 연성해석을 실시하여 방사소음수준을 예측하고, 실험을 통한 계측결과와 비교하였다.

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비소음 측정을 이용한 저소음 축류홴 설계 (Design of Low Noise Axial Flow Fan Using Specific Sound Presssure Level)

  • 김창준;이동익
    • 소음진동
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    • 제10권5호
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    • pp.873-879
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    • 2000
  • Experimental investigation was conducted to study the effects of pitch angle maximum camber on the performance and noise of an axial-flow fan used in outdoor-unit of air -conditioner. For this study the axial-flow fan whose pitch angle can be varied was made and the Specific sound Pressure Level and other coefficients were measured using the anechoic fan tester. It is found that pitch angle affects more severly than the maximum camber on the fan performance. On the while the maximum camber affects much on the specific sound power level. Present results show that it is important to choose the optimum pitch angle and maximum camber to design the high-performance and low-noise axial-flow fan and specific noise measured in the anechoic fan tester can be sued effectively for the design of low-noise fan.

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고속버스의 환기구 형태에 따른 환기량 분석 (Analysis on the Ventilation Rate of Express Bus according to the Geometry of Vent)

  • 신인환;유호천
    • 한국태양에너지학회:학술대회논문집
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    • 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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    • pp.174-178
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    • 2011
  • This paper deals with the free cooling system of express bus using natural energy source in order to improve the room air quality and save cooling energy. In an express bus, there are may passengers in unit area, requiring the improvement of air quality and giving higher energy saving efficiency. Particularly, the express buses running fast make it easy to take in outdoor air at a flow rate controllable with a damper mechanism. This paper proposes the analysis on the air flow achieved by a damper controlled vertically and horizontally in order not to deteriorate the ride comfort of the passengers.

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멀티형 냉방시스템의 압축기 제어 (Compressor Control of a Multi-type AIr Conditioning System)

  • 한도영;권형진
    • 설비공학논문집
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    • 제13권8호
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    • pp.780-786
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    • 2001
  • For the compressor speed control of a multi-type air conditioning system, a fuzzy control algorithm was developed. The sum of zone temperature errors and its derivative were used as input variables, and the compressor speed was selected as the output variable. To test the effectiveness of the control algorithm, one outdoor environmental chamber and four indoor environmental chambers were used. In the chambers the zone temperature step change test and the indoor unit change over test were performed. Test results showed that, for the control of compressor speed, the fuzzy control algorithm was more effective than the conventional proportional control algorithm for the energy conservation.

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공동주택용 온수난방 시스템의 에너지해석 및 제어특성 (The Energy Analysis and Control Characteristics of a Hot Water Heating System for Apartment Houses)

  • 장효환;안병천
    • 설비공학논문집
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    • 제8권1호
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    • pp.76-87
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    • 1996
  • Energy analysis for the hot water heating control system of apartment house complex is accomplished by computer simulation. Mathematical model of a boiler, pipe network and a unit-house is developed. The effects of heating control methods on the heating performance and energy consumption of the system are investigated. The heating control methods considered in this study are a continuous heating control, and on-off heating control and an intermittent heating control methods. For each control method, the effects of an outdoor temperature, indoor temperature sensing position and the capacities of the boilers and circulating pumps on the heating performance and energy consumption are obtained and "the best" control method is recommended.commended.

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여성전문병원 병동부의 거주성 향상을 위한 건축 계획적 연구 (A Study on the Architectural Planning for the Habitability of Women's Hospital ward)

  • 박승환;홍성우;최무혁
    • 한국주거학회논문집
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    • 제18권2호
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    • pp.29-38
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    • 2007
  • The purpose of this study was to provide the basic data for architectural planning through survey about the ward of women's hospital. This study considered the concept of women's hospital through theoretical consideration and analysed a blueprint of 30 cases about typical plan type, the size and layout of patient-room, space allocation and circulation. And then a survey of patients has to identify their needs. Because the rate of composition of an upper grade patient-room in women's hospital is higher than that of general hospital to improve habitability in ward needs not only the importance of the planing of patient-room itself, but also providing a small courtyard, day-room between the patient-rooms or outdoor terrace. When patient moves it was provided visual comfort and strengthen social exchange. Also, physical environment has to reflect mother's psychological needs and diversity by individuality in unit is essential to planning.

A-GPS (Assisted GPS), is this the system we need for indoor location & navigation?

  • Magnusson, Lars E;Gronqvist, Oskar
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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    • pp.67-70
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    • 2006
  • For a long time the GSM and GPS world has been living side by side. There have been some half hearted attempts to invoke the GPS unit into GSM units but performance and usability has suffered. The A-GPS approach is interesting and we wanted to verify general performance for fleet application and alarm/emergency situations. The result is now promising but still more to enhancements are anticipated. We achieved near acceptable availability (${\sim}70%$) under indoor conditions. Accuracy was as anticipated (50-100 meter) as we are using reflected signals. Time to first fix is in general good in outdoor conditions but too long for indoor conditions (45-60 seconds). We would like manufactures to put some more effort to get better performance in the future as test with Nordnav high sensitivity measurement system proves that conditions indoor are at a level where better performance should be possible.

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공동주택 하자사례 분석에 관한 연구 (The Study on Case Analysis of an Apartment House Defects)

  • 이희두;이해진;김진호;임남기
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2001년도 학술논문발표회
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    • pp.130-135
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    • 2001
  • In this study, I have researched into the causes of defects in apartment house, The results of this study are listed below. (1) Water leakages which result from land sinking and cracks, results of misuse of back filling method, are the main reason of defects in civil engineering work and architectural work. (2) Inexperience and unwillingness are the main reason of defects in plaster work. (3) In windows work and painting work, the main reasons are lacks of precision construction and efflorescence resulting from outdoor air, respectively. (4) Defects in waterproofing work and electric work result from fault construction by low unit Costs. (5) Equipment work requires uses of standardized construction materials and management, and landscape architecture work requires minimizing human mistakes, for instance, degin carelessness. For the reasons stated above, the causes of defects in apartment house are insufficient construction labors, inferior construction materials, urgent construction process time, and conscientiousless industrialists who only seek after a profit margin.

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멀티에어컨의 성능해석 프로그램 개발 (Development of Simulation Program for Multi-Air conditioner)

  • 정백영;고재윤;박병덕;임장순
    • 태양에너지
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    • 제20권1호
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    • pp.63-72
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    • 2000
  • In this study, theoretical simulation method for the steady state characteristics of a refrigeration cycle which consists of one condenser and multi-evaporator (Multi-air conditioner) is presented. The simulation was performed for a typical multi-air conditioning system consisted one outdoor unit with air-cooled condenser, compressor, linear electric expansion valve and bypass circuit and connected three-evaporators (three indoor units). The simulation results are good agreement with those of experiments within 5 $\sim$ 10% at the given system operation conditions which are condensing pressure, evaporating pressure, sub-cooled degree of condenser, superheated degree, discharge temperature of compressor and pulse of linear electric expansion valve.

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