Refrigeration and Air Conditioning 3 E Part 7 pps

... hygiene, or the cheese will be damaged. Some cheeses can be frozen for long-term storage, but must then be allowed to thaw out gradually and complete their ripening before release to the market. Other ... heat exchange between milk entering and leaving the process, hot water and chilled water, in plate heat exchangers (see Figure 17. 1) in the following stages: Figure 17. 1 Plate heat e...

Ngày tải lên: 12/08/2014, 00:20

... connecting the inner and outer tappings to the ends of the manometer, the difference will be the velocity pressure. Figure 27. 2 Vertical and inclined manometers Figure 27 .3 Pitot tube Sensitive and ... the outlet or on both sides of the fan. Such treatment needs to be selected for the particular application regarding frequency of the generated noise and the degree of attenuation r...

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... condensation or ice on cold surfaces. 34 .6 Excess condenser pressure This is the greatest cause of excess power and loss of duty in a refrigeration system. Causes are: 33 0 Refrigeration and Air- Conditioning 31 .6 ... the process exceeds the load. (See Figure 31 .2.) The range of the control will therefore be the differential of the detector plus the upper and lower oversho...

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... the need, based on the options presented. No attempt should be made to reach a decision until these have been evaluated. Index 37 7 Thermal electric expansion valve 102 Thermal storage, 152 Thermo-electric ... temperature difference between the refrigerant and the cooled medium. Since the latter is changing in temperature as it passes over the cooler surface (see Section 1.8), an accura...

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... Maintenance. Service. Fault-finding. Training 33 8 34 Efficiency and economy in operation 35 1 35 Catalogue selection 35 7 Appendix Units of measurement 36 7 References 36 9 Index 37 3 vi Contents The refrigeration ... load estimation 2 63 27 Air movement 2 73 28 Air- conditioning methods 2 97 29 Dehumidifiers and air drying 31 6 30 Heat pumps. Heat recovery 3...

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... contributes CO 2 emission to the atmosphere. The choice of refrigerant is therefore about the efficiency of the refrigerant and the efficiency of the refrigeration system. The less the amount of energy ... copper. This chapter is about the new refrigerants and the new attitude needed in design, maintenance and servicing of refrigeration equipment. 3. 2 Ideal properties for a refri...

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... covered by the provisions of BS.4 434 :1980 and require safety pressure relief devices as outlined in Section 6.10. In cases where there is no shut-off valve between the condenser and receiver, ... the condenser heat. If the mass flow is reduced, the temperature rise must increase, raising the condensing temperature and pressure to give lower plant efficiency. In practice, the temperatu...

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... and shorten the working life. 11.11 Site pressure safety tests Site-erected pipework, once complete, must be pressure tested for safety and freedom from leaks. Pressures will be 1 .3 times the 118 Refrigeration ... higher condenser pressure is to increase the compression ratio and so reduce the volumetric efficiency and increase the power. There will also be the effect of the gas b...

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... provide an insulated and refrigerated enclosure suitable for the handling and storage of perishable goods, at some predetermined temperature. The shape and size of the cold store will depend on: 1. ... a eutectic solution, and these are frozen down by placing these elements in the domestic deep-freeze cabinet. Once frozen, they can be used in picnic baskets, etc., for the short-term s...

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... are based on observed practice. The parameters are the size of the store, the enthalpy difference between inside and outside air, and the usage of the doors. The latter is affected by the existence ... process analysed to decide representative rates. Assumptions should be stated and agreed by the parties concerned, since these estimates are to form the basis for the selection of the re...

Ngày tải lên: 12/08/2014, 00:20