Heat-exchanger design and switching-frequency effects on the performance of a continuous type solar adsorption chiller

Voyiatzis, E; Palyvos, JA; Markatos, N-C

dc.contributor.author	Voyiatzis, E	en
dc.contributor.author	Palyvos, JA	en
dc.contributor.author	Markatos, N-C	en
dc.date.accessioned	2014-03-01T01:28:33Z
dc.date.available	2014-03-01T01:28:33Z
dc.date.issued	2008	en
dc.identifier.issn	0306-2619	en
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/18873
dc.subject	Dimensionless numbers	en
dc.subject	Heat exchanger	en
dc.subject	Silica gel	en
dc.subject	Solar adsorption chiller	en
dc.subject	Solar air-conditioning	en
dc.subject	Switching frequency	en
dc.subject.classification	Energy & Fuels	en
dc.subject.classification	Engineering, Chemical	en
dc.subject.other	Adsorption	en
dc.subject.other	Cooling	en
dc.subject.other	Cooling systems	en
dc.subject.other	Electric power supplies to apparatus	en
dc.subject.other	Optimization	en
dc.subject.other	Switching frequency	en
dc.subject.other	Turbulent flow	en
dc.subject.other	Adsorption chiller	en
dc.subject.other	Biot numbers	en
dc.subject.other	Continuous operations	en
dc.subject.other	Cooling capacity	en
dc.subject.other	Cycle time	en
dc.subject.other	Dimensionless numbers	en
dc.subject.other	Exchanger design	en
dc.subject.other	Fourier numbers	en
dc.subject.other	Frequency effects	en
dc.subject.other	Heat exchanger	en
dc.subject.other	Maximum cooling capacity	en
dc.subject.other	One-dimensional modeling	en
dc.subject.other	Optimal operations	en
dc.subject.other	Parametric studies	en
dc.subject.other	Silica gel	en
dc.subject.other	Solar adsorption chiller	en
dc.subject.other	Solar air-conditioning	en
dc.subject.other	Space velocities	en
dc.subject.other	System performances	en
dc.subject.other	Switching	en
dc.subject.other	adsorption	en
dc.subject.other	cooling	en
dc.subject.other	design	en
dc.subject.other	heat transfer	en
dc.subject.other	one-dimensional modeling	en
dc.subject.other	performance assessment	en
dc.subject.other	silica	en
dc.subject.other	thermodynamics	en
dc.title	Heat-exchanger design and switching-frequency effects on the performance of a continuous type solar adsorption chiller	en
heal.type	journalArticle	en
heal.identifier.primary	10.1016/j.apenergy.2008.03.005	en
heal.identifier.secondary	http://dx.doi.org/10.1016/j.apenergy.2008.03.005	en
heal.language	English	en
heal.publicationDate	2008	en
heal.abstract	A transient one-dimensional model, capable of describing the performance of a newly-introduced adsorption chiller with continuous operation, is developed. Since the cycle time and the switching frequency have a great influence on chiller performance, a non-dimensional switching frequency is introduced and a systematic parametric study is carried out in order to determine regions of optimal operation. An optimization based on the thermodynamic efficiency yields a lower switching frequency than an optimization based on the maximum cooling capacity. In addition, the effect of the heat-exchanger design parameters on system performance is explored. An increase of either the bed's Fourier number or the thermofluid's Nusselt number has a positive effect on both COP and cooling capacity. An improvement of system performance can also be achieved by decreasing either the thermofluid's Fourier number or the bed's Biot number. Finally, the effect of space velocity of the thermofluid exhibits the most interesting behavior; an increase of the space velocity has a positive effect on cooling capacity and a negative effect on COP. (C) 2008 Elsevier Ltd. All rights reserved.	en
heal.publisher	ELSEVIER SCI LTD	en
heal.journalName	Applied Energy	en
dc.identifier.doi	10.1016/j.apenergy.2008.03.005	en
dc.identifier.isi	ISI:000259653800010	en
dc.identifier.volume	85	en
dc.identifier.issue	12	en
dc.identifier.spage	1237	en
dc.identifier.epage	1250	en