Page 432 - Mechanical Engineers' Handbook (Volume 4)

Mechanical Engineers’ Handbook: Energy and Power, Volume 4, Third Edition.

Edited by Myer Kutz

Copyright  2006 by John Wiley & Sons, Inc.

CHAPTER 12
REFRIGERATION
Dennis L. O’Neal
Department of Mechanical Engineering
Texas A&M University
College Station, Texas
1 INTRODUCTION 421 6 INDIRECT REFRIGERATION 440
2 BASIC PRINCIPLES 422 7 SYSTEM COMPONENTS 444
7.1 Compressors 444
3 REFRIGERATION CYCLES AND 7.2 Condensers 451
SYSTEM OVERVIEW 423 7.3 Evaporators 452
3.1 Closed-Cycle Operation 423 7.4 Expansion Devices 454
3.2 Open-Cycle Operation 426
3.3 Losses in Refrigeration Cycles 428 8 DEFROST METHODS 459
8.1 Hot Refrigerant Gas Defrost 459
4 REFRIGERANTS 429 8.2 Air, Electric, and Water Defrost 459
4.1 Regulations on the Production
and Use of Refrigerants 433 9 SYSTEM DESIGN
4.2 Refrigerant Selection for the CONSIDERATIONS 460
Closed Cycle 434
4.3 Refrigerant Selection for the 10 REFRIGERATION SYSTEM
Open Cycle 436 SPECIFICATIONS 461
5 ABSORPTION SYSTEMS 437 REFERENCES 463
5.1 Water–Lithium Bromide
Absorption Chillers 437
5.2 Ammonia–Water Absorption
Systems 440

1 INTRODUCTION
Refrigeration is the use of mechanical or heat-activated machinery for cooling purposes. The
use of refrigeration equipment to produce temperatures below 150 C is known as cryo-
1
genics. When refrigeration equipment is used to provide human comfort, it is called air
conditioning. This chapter focuses primarily on refrigeration applications, which cover such
diverse uses as food processing and storage, supermarket display cases, skating rinks, ice
manufacture, and biomedical applications such as blood and tissue storage or hypothermia
used in surgery.
The first patent on a mechanically driven refrigeration system was issued to Jacob Per-
2
kins in 1834 in London. The system used ether as the refrigerant. The first viable com-
mercial system was produced in 1857 by James Harrison and D. E. Siebe and used ethyl
ether as the refrigerant. 2
Refrigeration is used in installations covering a broad range of cooling capacities and
temperatures. While the variety of applications results in a diversity of mechanical specifi-
cations and equipment requirements, the methods for producing refrigeration are well stan-
dardized.

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