Refrigeracion

Refrigeration and
Air-Conditioning

Refrigeration: The process of removing heat.
Air-conditioning: A form of air treatment whereby temperature,
humidity, ventilation, and air cleanliness are all controlled within
limits determined by the requirements of the air conditioned
enclosure.

Refrigeration and
Air-Conditioning

Contents

1
2
3
4
5
6
7
8
9
10
11
12
13
1415
16
17
18
19
20
21
22
23
24
25

Fundamentals 1
The refrigeration cycle 14
Refrigerants 28
Compressors 36
Oil in refrigerant circuits 57
Condensers and water towers 63
Evaporators 83
Expansion valves 93
Controls and other circuit components 104
Selection and balancing of components 121
Materials. Construction. Site erection 131
Liquid chillers. Ice. Brines. Thermal storage144
Packaged units 154
Refrigeration of foods. Cold storage practice 162
Cold store construction 170
Refrigeration in the food trades – meats and fish 188
Refrigeration for the dairy, brewing and soft drinks
industries 193
Refrigeration for fruit, vegetables and other foods 201
Food freezing. Freeze-drying 205
Refrigerated transport, handling and distribution 208
Refrigeration loadestimation 214
Industrial uses of refrigeration 223
Air and water vapour mixtures 227
Air treatment cycles 240
Practical air treatment cycles 255

vi

26
27
28
29
30
31
32
33
34
35

Contents

Air-conditioning load estimation 263
Air movement 273
Air-conditioning methods 297
Dehumidifiers and air drying 316
Heat pumps. Heat recovery 320
Control systems 324
Commissioning 333Operation. Maintenance. Service. Fault-finding. Training 338
Efficiency and economy in operation 351
Catalogue selection 357

Appendix Units of measurement 367
References 369
Index 373

Preface

Refrigeration and its application is met in almost every branch of
industry, so that practitioners in other fields find that they have to
become aware of its principles, uses andlimitations. This book aims
to introduce students and professionals in other disciplines to the
fundamentals of the subject, without involving the reader too deeply
in theory. The subject matter is laid out in logical order and covers
the main uses and types of equipment. In the ten years since the last
edition there have been major changes in the choice of refrigerants
due to environmental factorsand an additional chapter is introduced
to reflect this. This issue is on-going and new developments will
appear over the next ten years. This issue has also affected servicing
and maintenance of refrigeration equipment and there is an increased
pressure to improve efficiency in the reduction of energy use. This
edition reflects these issues, whilst maintaining links with the past
for usersof existing plant and systems. There have also been changes
in packaged air-conditioning equipment and this has been introduced
to the relevant sections. The book gives worked examples of many
practical applications and shows options that are available for the
solution of problems in mechanical cooling systems. It is not possible
for these pages to contain enough information to design acomplete
refrigeration system. The design principles are outlined. Finally,

1 Fundamentals

1.1

Basic physics – temperature

The general temperature scale now in use is the Celsius scale, based
nominally on the melting point of ice at 0°C and the boiling point
of water at atmospheric pressure at 100°C. (By strict definition, the
triple point of ice is 0.01°C at a pressure of 6.1 mbar.)On the
Celsius scale, absolute zero is – 273.15°C.
In the study of refrigeration, the Kelvin or absolute temperature scale
is also used. This starts at absolute zero and has the same degree
intervals as the Celsius scale, so that ice melts at + 273.16 K and
water at atmospheric pressure boils at + 373.15 K.

1.2

Heat

Refrigeration is the process of removing heat, and the practical...