Second law analysis of a stirling cryocooler with optimal design of the regenerator and losses

Rogdakis, ED; Bormpilas, NA

dc.contributor.author	Rogdakis, ED	en
dc.contributor.author	Bormpilas, NA	en
dc.date.accessioned	2014-03-01T02:41:58Z
dc.date.available	2014-03-01T02:41:58Z
dc.date.issued	2001	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/30712
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-1542287592&partnerID=40&md5=20d25aa05f26e38a2fc4a42906469086	en
dc.relation.uri	http://www.scopus.com/inward/record.url?eid=2-s2.0-1542287592&partnerID=40&md5=20d25aa05f26e38a2fc4a42906469086	en
dc.subject	Regenerator and losses	en
dc.subject	Stirling cryocooler	en
dc.subject	Stirling cycle	en
dc.subject	Stirling engine	en
dc.subject.other	Heat losses	en
dc.subject.other	Helium	en
dc.subject.other	Mathematical models	en
dc.subject.other	Matrix algebra	en
dc.subject.other	Regenerators	en
dc.subject.other	Reynolds number	en
dc.subject.other	Stirling cycle	en
dc.subject.other	Stirling engines	en
dc.subject.other	Thermal diffusion	en
dc.subject.other	Thermal expansion	en
dc.subject.other	Regenerator and losses	en
dc.subject.other	Stirling cryocoolers	en
dc.subject.other	Thermal engines	en
dc.subject.other	Mechanical engineering	en
dc.title	Second law analysis of a stirling cryocooler with optimal design of the regenerator and losses	en
heal.type	conferenceItem	en
heal.publicationDate	2001	en
heal.abstract	The aim of the research in this paper is a second law analysis of a Stirling cryocooler. A one-dimensional model is proposed for the simulation of the gas flow in the expansion space, the regenerator, the warm-end, the compression space and the compressor. Helium gas is selected as the working medium. An algorithm has been developed considering parametrically the most from the main operational tasks of the thermodynamic cycle. Performance indices such as heat input, efficiency, external dimensions of the engine and technical requirements are taken into account as constraints. Engine operating parameters i.e. speed, external temperature, mean pressure are fixed. The regenerator loss has a critical influence on the cryocooler efficiency and the reduction of this kind of internal irreversibilities is extremely difficult due to the generator is subject to rapidly cycling flows accompanied by steep temperature gradients and large pressure variations. The second flow analysis of the regenerator identifies two principal losses, the irreversible internal heat transfer into the solid matrix and the hydraulic resistance. An optimization technique leads to entropy generation charts, extremely useful for a good design of the regenerator. Finally the main thermodynamic characteristics (net refrigeration, power input and the coefficient of performance) of the cryocooler are given both cases with and without external and internal irreversibilities.	en
heal.journalName	American Society of Mechanical Engineers, Process Industries Division (Publication) PID	en
dc.identifier.volume	6	en
dc.identifier.spage	181	en
dc.identifier.epage	189	en