1. 자동차공학 및 실습 자동차 냉난방장치
전남대학교 기계시스템공학부
교수 임 명 택

2. 자동차 냉난방 장치(Crouse & Anglin 2, 55장)
환기, 난방 및 냉방
(HVAC; Heating, Ventilation, and Air conditioning)

3. 냉난방 장치 (HVAC) Ventilating and Heating (환기와 난방)
Uncontrolled ventilation : 창문 개방에 의한 환기
Controlled ventilation
Ram-air ventilation
Power ventilating sys. : blower motor & fan (송풍기)
Fig. 55-1

4. 냉난방 장치 (HVAC) Ventilating and Heating (환기와 난방)
Passenger-compartment Heater (객실 히터)
Heater core
Heater control
Function control
Temperature control
Blower speed control
Fig. 55-3
Fig. 55-1

5. 냉난방 장치 (HVAC) Ventilating and Heating (환기와 난방)
Passenger-compartment Heater (객실 히터)
Valves for control
Function control
Temperature control
Defroster nozzles
Fig. 55-4
Fig. 55-2

6. 냉난방 장치 (HVAC) Ventilating and Heating (환기와 난방) Rear window defogger
Heated windshield
Fig. 55-5
Fig. 55-6

7. 냉난방 장치 (HVAC) Ventilating and Heating (환기와 난방)
Solar-powered ventilation
Photovoltaic (or solar) cells connected in series/parallel
Output drives a small ventilating fan during parking
Or charges vehicle battery on cooler days
Ventilation-air filter
Fig. 55-7

8. 냉난방 장치 (HVAC) Refrigeration and Cooling (냉동과 냉각)
Automotive air conditioner (자동차 에어컨)
기계식 증기압축냉동장치로 승객실의 열을 제거
Fig. 55-8

9. 냉난방 장치 (HVAC) Refrigeration and Cooling (냉동과 냉각)
Change of phase (상 변화) : 고체, 액체, 기체 사이의 변화
다량의 열을 흡수(증발) 혹은 방출(응축) 동반.
Evaporation (증발) : 액체가 열을 흡수하며 기화하는 것.
온도가 높고 압력이 낮을수록 활발.
Condensation (응축) : 기체가 열을 내놓으며 액화하는 것.
온도 낮고 압력 높을수록 활발.

10. 냉난방 장치 (HVAC) Refrigeration and Cooling (냉동과 냉각) Heat transfer (열전달)
conduction (전도)
convection (대류)
radiation (복사).

11. 냉난방 장치 (HVAC) Refrigeration and Cooling (냉동과 냉각) Fig. 55-11
Basic refrigeration cycle (기본 냉동 사이클)
hi-pres. liquid (고압 액체), lo-pres. Liquid (저압 액체),
lo-pres. vapor (저압 증기), hi-pres vapor (고압 증기)
Fig

12. 냉난방 장치 (HVAC) Refrigeration and Cooling (냉동과 냉각) Fig. 55-11
Accumulator (used w/ orifice)
trap liquid refrigerant & absorb moisture)
Receiver-dryer (used w/ expansion valve)
small reservoir for liquid refrigerant, absorb moisture
Fig

13. 냉난방 장치 (HVAC) Refrigeration and Cooling (냉동과 냉각) refrigerant (냉매) :
저온{-(26~30)℃}에서 액체/증기로 존재하는 물질
필요한 성질 : 무독성, 불연성, 불활성, 금속/고무 등에 안전
오존층 파괴 현상과 대체냉매
CFC (chlorofluorocarbon, Feon, R-12)
Hydrofluorocarbon (R-134a)

14. 냉난방 장치 (HVAC) Compressors and comp. clutch (컴프레서)
Type of compressors (컴프레서의 종류) :
Rotary(swash or wobble plate), Piston-crank, Vane, Scroll, etc
Fixed- or Variable-displacement
Fig
Fig

15. 냉난방 장치 (HVAC) Compressors and compressor clutch
Solenoid-type magnetic clutch in pulley (stationary coil)
Pulley turns w/ shaft or alone (when off, or cycling)
Fig
Fig

16. 냉난방 장치 (HVAC) Compressors and compressor clutch
Air-conditioner safety devices (에어컨 안전 기기)
Ambient-temperature switch : opens comp.-clutch circuit below preset amb. Temp.
Low-pressure cutoff switch : disenges comp clutch if evap press. gets too low (lost refrigerant or oil)
High pressure relief valve : opens when hi-side press. gets too high (condenser blocked or system overcharged)
High-pressure cutoff switch : disengages comp when discharge press gets too high.
Thermal limiter and superheat switch : melts & opens comp clutch switch circuit on low press & high temp (lost refrigerant)

17. 냉난방 장치 (HVAC) Heater-Air-conditioner
Automotive air-conditioners (자동차 에어컨)
Cleans, cools, dries, and circulates passenger compartment air.
Powered by engine; reduced engine performance & fuel economy.
Manually controlled or automatically controlled.
Fig
Fig

18. 냉난방 장치 (HVAC) Heater-Air-conditioner
Electronic Automatic temperature control (전자동 에어컨)
Fig

19. 자동차공학및실습 끝.
고생하셨습니다.