Автор: Dr. Claes Stenhede/Alfa Laval AB.
Тип документа: Справочник | pdf.
Популярность: 0.17 %
Размер файла: 7 Mb.
Год издания: June 1st, 2001.
This is the fourth edition of the manual. Since the first edition, there has been an intense debate about refrigerants, both new, with and without glide and natural, such as pro-pane and ammonia. This debate has influenced the devel-opment of equipment including plate heat exchangers.
One of the effects on PHE's has been that the old boundary between the small BPHE for halogenated hydrocarbons in direct expansion systems and the large semiwelded PHE for ammonia in flooded systems has disappeared. Ammonia is increasingly used in direct expansion systems in nickel brazed PHE's and there are large brazed PHE's suitable for flooded systems.
Hence, this new edition deals not only with brazed PHE's but also with the larger welded and semi-welded PHE's. After all, the thermal and hydraulic properties are the same for all PHE's, from the smallest brazed to the largest gasketed.
The purpose of the manual is to provide an understanding of the properties of the brazed and semi-welded plate heat exchanger in order to design, install, operate, and trouble-shoot them correctly
This Technical Reference Manual is divided into two sec-tions. The first - the present booklet - contains general in-formation about BPHE's in refrigeration systems. It com-prises eight chapters and four appendices. Although all the chapters can be studied individually, some cross-references are made.
The second part - the product catalogue - contains specific data about the product range.
For the content of this manual, I have had the invaluable help of colleagues within Alfa Laval, in both Italy and abroad, but especially Bernard Pasquier, Loris Sartori, Mats Stromblad and Alvaro Zorzin to whom I express my thanks.
Finally, I thank an understanding wife and son for their patience during all the working evenings. Especially Eric thinks now that a father comes with an integrated laptop.
1. Applications. The Basic Refrigeration Cycles and Applications.
1. The pressure-enthalpy diagram.
2. The basic cycle.
3. Intercoolers & subcoolers.
4. The components.
4.1. The expansion process and devices.
4.2. The compressor.
4.3. Evaporators, condensers and interchangers.
4.4. The interconnecting pipe work.
5. The flash economizer cycle.
6. The evaporator economizer cycle.
7. The real versus the ideal refrigeration cycle.
8. Definition of capacity and coefficient of performance.
9. Improvement of the cycles and the use of PHE in these.
10. Subcooler/superheater cycle.
11. The cascade cycle.
12. The absorption cycles.
12.3. The ammonia/water system.
12.4. The water/lithium bromide system.
13. Heat exchanger applications in a large supermarket.
14. Reversible systems.
14.1.1. Cold stores.
14.1.2. Heat pumps.
14.1.3. Reversible A/C-Heat pumps units.
14.2. Design considerations.
14.2.1. Co- vs. counter current flow.
14.2.2. Freezing risk at the flow reverse.
14.2.3. Suction line separators.
14.2.4. Condensate subcoolers.
14.2.5. Oil separators, sight glasses and filter/drier;
14.2.6. Liquid receivers in reversible systems.
14.2.7. Installation of the liquid receiver.
14.2.8. One or two TEV systems.
14.2.9. Systems with a liquid receiver.
14.2.10. Systems without a liquid receiver.
15. Sea water cooled systems.
15.1. What is a SECOOL system?
15.2. Direct vs. indirect systems.
16. Soluble oil in flooded systems.
16.1. The oil evaporator.
16.2. The oil cooler.