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Accession Number ADA562695
Title High Speed Compressor Study.
Publication Date Dec 2011
Media Count 47p
Personal Author C. R. Stone M. Dadd P. Bailey
Abstract The project examined several means of increasing the operating frequency of cryocoolers, with the goal of increasing the power per unit mass (or volume) of cryocooler compressors. A small increase in spring stiffness can be obtained by improving the design, materials and manufacturing techniques of the mechanical springs (flexures), but the consequent increase in operating frequency is small. The use of an auxiliary gas spring to increase frequency is studied in detail, particularly with respect to the compression losses and clearance seal losses. A gas spring can be used to give a very large increase in compressor operating frequency, but at these high frequencies these losses tend to become large, with a consequent reduction in efficiency. Use of a smaller gas spring, with lower losses, but a reduced increase in frequency, will provide a better design for most applications. A design method is described for the embodiment of a gas spring, and a worked example is given, showing how the power output of a particular compressor can be doubled, with a 40% increase in compressor size, and a much smaller increase in mass.
Keywords Compressor operating frequency
Compressors
Cryocoolers
Foreign reports
Gas springs
Mechanical springs
Springs
Stiffness
Thermodynamics
Thermophysics
United kingdom


 
Source Agency Non Paid ADAS
NTIS Subject Category 89B - Architectural Design & Environmental Engineering
41J - Tooling, Machinery, & Tools
Corporate Author Oxford Univ. (England). Dept. of Engineering Science.
Document Type Technical report
Title Note Final rept. 1 Jan 2011-1 Jan 2012.
NTIS Issue Number 1225
Contract Number FA8655-11-1-3032

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