File Download
  Links for fulltext
     (May Require Subscription)
Supplementary

Article: Wind tunnel measurements of turbulent boundary layer flows over arrays of ribs and cubes

TitleWind tunnel measurements of turbulent boundary layer flows over arrays of ribs and cubes
Authors
KeywordsFrequency spectra
Momentum fluxes
Quadrant analyses
Turbulent flows
Wind tunnel laboratory experiments
Issue Date2018
PublisherSpringerOpen.
Citation
Geoscience Letters, 2018, v. 5, p. 1-10 How to Cite?
AbstractUnderstanding the effect of building morphology on the flow aloft is important to the ventilation and pollutant removal in cities. This study examines the dynamics over hypothetical urban areas in isothermal conditions using wind tunnel experiments. Different configurations of rib-type and cube-type arrays are designed to model hypothetical rough urban surfaces. The mean and fluctuating velocities are measured by hot-wire anemometry with X-wire probes. The results show that significant variations of fluctuating velocities and momentum fluxes are clearly observed in the near-wall region, depicting the inhomogeneous flow in response to the presence of roughness elements in the lower part of turbulent boundary layer. Comparing the variables over different rough surfaces, the roof-level fluctuating velocities and momentum fluxes increase with increasing surface roughness. Quadrant analyses and frequency spectra collectively suggest that the fresh air entrainment and aged air removal are enhanced over rougher surfaces. Larger energy-carrying turbulence motions contribute mostly to the more efficient ventilation over urban areas.
Persistent Identifierhttp://hdl.handle.net/10722/264194
ISSN
ISI Accession Number ID

 

DC FieldValueLanguage
dc.contributor.authorMo, Z-
dc.contributor.authorLiu, CH-
dc.date.accessioned2018-10-22T07:51:02Z-
dc.date.available2018-10-22T07:51:02Z-
dc.date.issued2018-
dc.identifier.citationGeoscience Letters, 2018, v. 5, p. 1-10-
dc.identifier.issn2196-4092-
dc.identifier.urihttp://hdl.handle.net/10722/264194-
dc.description.abstractUnderstanding the effect of building morphology on the flow aloft is important to the ventilation and pollutant removal in cities. This study examines the dynamics over hypothetical urban areas in isothermal conditions using wind tunnel experiments. Different configurations of rib-type and cube-type arrays are designed to model hypothetical rough urban surfaces. The mean and fluctuating velocities are measured by hot-wire anemometry with X-wire probes. The results show that significant variations of fluctuating velocities and momentum fluxes are clearly observed in the near-wall region, depicting the inhomogeneous flow in response to the presence of roughness elements in the lower part of turbulent boundary layer. Comparing the variables over different rough surfaces, the roof-level fluctuating velocities and momentum fluxes increase with increasing surface roughness. Quadrant analyses and frequency spectra collectively suggest that the fresh air entrainment and aged air removal are enhanced over rougher surfaces. Larger energy-carrying turbulence motions contribute mostly to the more efficient ventilation over urban areas.-
dc.languageeng-
dc.publisherSpringerOpen. -
dc.relation.ispartofGeoscience Letters-
dc.rightsThis work is licensed under a Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International License.-
dc.subjectFrequency spectra-
dc.subjectMomentum fluxes-
dc.subjectQuadrant analyses-
dc.subjectTurbulent flows-
dc.subjectWind tunnel laboratory experiments-
dc.titleWind tunnel measurements of turbulent boundary layer flows over arrays of ribs and cubes-
dc.typeArticle-
dc.identifier.emailLiu, CH: chliu@hkucc.hku.hk-
dc.identifier.authorityLiu, CH=rp00152-
dc.description.naturepublished_or_final_version-
dc.identifier.doi10.1186/s40562-018-0115-x-
dc.identifier.hkuros294656-
dc.identifier.volume5-
dc.identifier.spage1-
dc.identifier.epage10-
dc.identifier.isiWOS:000445949000001-
dc.publisher.placeGermany-

Export via OAI-PMH Interface in XML Formats


OR


Export to Other Non-XML Formats