SCREW COMPRESSORS IN REFRIGERATION AND AIR CONDITIONING Professor
نویسنده
چکیده
Recent advances in the techniques of manufacture of vital parts, such as rotors and bearings, have enabled improvements to be made to screw compressors, which were difficult to imagine only a few years ago. This has inevitably influenced the prospects for these machines in refrigeration and air conditioning applications. Some aspects of this are presented, together with well known but not always fully appreciated principles of rational screw compressor design. Despite the improvements already achieved, there is a continuing need to make refrigeration compressors operate more quietly, reliably and with higher efficiencies over a long service life. This can best be done, with the minimum of experimental development, by consideration of all the relevant variables that affect their operation, at the design stage. An evolving means of doing this is to include all these factors simultaneously in multivariable optimisation procedures and examples of these are included. Several innovative ideas, some of them not necessarily new, but only recently considered or put into practice, are reviewed and it is shown how the scope for such machines can be widened by performing more than one function within a single pair of rotors, such as two stage compression or combining compression with expansion.
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تاریخ انتشار 2004