Bài giảng Chapter 6: Condenser

Bài giảng Chapter 6: Condenser với mục tiêu giúp cho sinh viên understand principle of some kind of condensers, đồng thời calculate and chose the condenser met the Calculate and chose the condenser met therequired capacity. Hy vọng tài liệu là nguồn thông tin hữu ích cho quá trình học tập và nghiên cứu của các bạn.
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Bài giảng Chapter 6: Condenser CHAPTER 6: CONDENSER Lecturer : ThS.Nguyễn Duy Tuệ12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 1 OBJECTIVES In this chapter, chapter student st dent can: can -Understand principle of some kind of condensers -Calculate Calculate and chose the condenser met the required capacity12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 2 REFERENCES [1]. Trane document [1] doc ment [2]. Kỹ thuật lạnh cơ sở - Nguyễn Đức Lợi12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 3 CONTENT AIR COOLED CONDENSER EVAPORATIVE CONDENSER WATER COOLED CONDENSER CONDENSER CALCULATION12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 4 AIR COOLED CONDENSER - The condenser is a heat exchanger that rejects heat from the refrigerant to air, air water, water or some other fluid. - The three common types of condensers are airair- cooled, water-cooled, and evaporative.12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 5 AIR COOLED CONDENSER - A typical air-cooled condenser uses propeller- type fans to draw outdoor air over a finned-tube finned tube heat transfer surface. - The temperature difference between the hot refrigerant vapor and the cooler outdoor air induces heat transfer. The resulting reduction in the heat content of the refrigerant vapor causes it to condense into liquid. - Within Withi the th final fi l few f l lengths th off condenser d t bi tubing (the subcooler), the liquid refrigerant is further cooled below the temperature at which it was condensed.12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 6 AIR COOLED CONDENSER12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 7 AIR COOLED CONDENSER Air cooled condenser without fan12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 8 AIR COOLED CONDENSER + Advantage : - It requires very little maintenance and does not require the freeze protection and water treatment that is necessary with a water water-cooled cooled condenser. - It is favored in areas that have an inadequate or costly water supply, or where the use of water for air conditioning is restricted. + Disadvantage : High condensing pressure12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 9 EVAPORATIVE CONDENSER A modification of the air-cooled condenser is the evaporative ti condenser. d Withi this Within thi device, d i th the refrigerant flows through tubes and air is drawn or blown over the tubes by a fan. fan The difference is that water is sprayed on the tube surfaces. As the air passes over the coil,, it causes a small p p portion of the water to evaporate. This evaporation process absorbs heat from the coil, causing the refrigerant vapor within the tubes to condense. The remaining water then falls to the sump to be recirculated and used again. again12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 10 EVAPORATIVE CONDENSER We can subcool the liquid by using some length of pipe submerged in the water sump or on the path of air flow12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 11 EVAPORATIVE CONDENSER + Evaporative condenser without fan : Water poured from the top to the surface of tube; then evaporate by adding heat from condenser. Hot water drop p to the sump; p; and drain out partly; then it is compensated by cool wate12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 12 EVAPORATIVE CONDENSER12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 13 WATER COOLED CONDENSER - The shell-and-tube is the most common type of water-cooled condenser. With this design, water is pumped through the tubes while the refrigerant vapor fills the shell space surrounding the tubes. tubes - As heat is transferred from the refrigerant to the water, water the refrigerant vapor condenses on the tube surfaces. The condensed liquid refrigerant then falls to the bottom of the shell.12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 14 WATER COOLED CONDENSER + Shell-tube water cooled condenser12/2015 Chapter 6: Condenser - ThS.Nguyễn Duy Tuệ 15 WATER COOLED CONDENSER - After the warm water leaves the condenser, it must either be disposed of (as in the case of using water from a well) or it must be cooled before it can be reused by the condenser. condenser In this example, example the condenser brings in [29°C] water and warms it up to [35 [35°C] C]. Before this water can be used again, ...