Show simple item record

dc.contributor.authorWright, John L.
dc.contributor.authorCollins, Michael R.
dc.contributor.authorNaylor, David
dc.contributor.authorForoushani, Seyed Sepehr Mohaddes
dc.date.accessioned2017-03-29 14:57:14 (GMT)
dc.date.available2017-03-29 14:57:14 (GMT)
dc.date.issued2017-01
dc.identifier.otherLV-17-C080
dc.identifier.urihttp://hdl.handle.net/10012/11597
dc.description© 2017 ASHRAE (www.ashrae.org). Published in ASHRAE Conference Papers, Winter Conference, Las Vegas, NV. For personal use only. Additional reproduction, distribution, or transmission in either print or digital form is not permitted without ASHRAE's prior written permission.en
dc.description.abstractIn order to characterize the resistor network that describes convective heat transfer on the indoor side of a complex fenestration system, three convection coefficients are needed. Although methods to obtain convection coefficients in glazing cavities are well established, the convection coefficients in the vicinity of an indoor-mounted attachment are not so readily available. In principle, convection coefficients of a three-resistor network cannot be obtained based on numerical solutions or measurement only. The ASHWAT models for simulating windows with attachments currently provide estimates of the three convection coefficients as functions of glass-to-shade spacing, based largely on known limits. Recently, a numerical technique, dubbed dQdT, was developed for evaluating the heat transfer coefficients of multi-temperature convection problems. This technique entails numerical solutions of the full set of governing equations and subsequent solutions of the energy equation with perturbed boundary conditions. In earlier work, dQdT was applied to a fenestration system with an indoor-mounted roller blind. To keep the flow laminar and the numerical solutions simple, a relatively short window was considered. Preliminary results suggested that ASHWAT gives good estimates of the convection coefficients and accurately predicts the general trends. Nevertheless, ASHWAT overestimated the glass-to-shade heat transfer coefficient for intermediate spacing, while underpredicting glass-to-air and shade-to-air heat transfer coefficients for larger spacings. The effect of spacing also seemed to be underestimated by ASHWAT. The present study was undertaken to further examine the accuracy of the ASHWAT estimates for windows with realistic dimensions, various glazing-attachment spacings and taking into account the transition of the flow to turbulence. Excellent agreement between the dQdT results and the ASHWAT predictions was obtained under summer design conditions, confirming the validity and utility of the current ASHWAT correlations. A minor adjustment to improve the accuracy of the current ASHWAT estimates is suggested.en
dc.description.sponsorshipSmart Net-Zero Energy Buildings strategic Research Network (SNEBRN) || Natural Science and Engineering Research Council (NSERC) of Canada || University of Waterlooen
dc.language.isoenen
dc.publisherAmerican Society of Heating, Refrigerating and Air-Conditioning Engineersen
dc.subjectFenestrationen
dc.subjectShadingen
dc.subjectConvectionen
dc.subjectSimulationen
dc.subjectdQdTen
dc.titleIndoor-Side Convection Coefficients for Complex Fenestration Systems with Roller Blindsen
dc.typeConference Paperen
dcterms.bibliographicCitationForoushani, S.S.M., Wright J.L., Collins M.R., Naylor D., 2017, “Indoor-Side Convection Coefficients for Complex Fenestration Systems with Roller Blinds,” 2017 ASHRAE Winter Conference (Las Vegas, USA),(2017)en
uws.contributor.affiliation1Faculty of Engineeringen
uws.contributor.affiliation2Mechanical and Mechatronics Engineeringen
uws.typeOfResourceTexten
uws.peerReviewStatusRevieweden
uws.scholarLevelFacultyen


Files in this item

Thumbnail

This item appears in the following Collection(s)

Show simple item record


UWSpace

University of Waterloo Library
200 University Avenue West
Waterloo, Ontario, Canada N2L 3G1
519 888 4883

All items in UWSpace are protected by copyright, with all rights reserved.

DSpace software

Service outages