Intercomparisons of experimental convective heat transfer coefficients and mass transfer coefficients of urban surfaces

Aya Hagishima, Jun Tanimoto, Ken Ich Narita

研究成果: Contribution to journalArticle

44 引用 (Scopus)

抜粋

The convective heat transfer coefficient (CHTC) of an urban canopy is a crucial parameter for estimating the turbulent heat flux in an urban area. We compared recent experimental research on the CHTC and the mass transfer coefficient (MTC) of urban surfaces in the field and in wind tunnels. Our findings are summarised as follows. (1) In full-scale measurements on horizontal building roofs, the CHTC is sensitive to the height of the reference wind speed for heights below 1.5 m but is relatively independent of roof size. (2) In full-scale measurements of vertical building walls, the dependence of the CHTC on wind speed is significantly influenced by the choice of the measurement position and wall size. The CHTC of the edge of the building wall is much higher than that near the centre. (3) In spite of differences of the measurement methods, wind-tunnel experiments of the MTC give similar relations between the ratio of street width to canopy height in the urban canopy. Moreover, this relationship is consistent with known properties of the flow regime of an urban canopy. (4) Full-scale measurements on roofs result in a non-dimensional CHTC several tens of times greater than that in scale-model experiments with the same Reynolds number. Although there is some agreement in the measured values, our overall understanding of the CHTC remains too low for accurate modelling of urban climate.

元の言語英語
ページ(範囲)551-576
ページ数26
ジャーナルBoundary-Layer Meteorology
117
発行部数3
DOI
出版物ステータス出版済み - 12 1 2005

All Science Journal Classification (ASJC) codes

  • Atmospheric Science

フィンガープリント Intercomparisons of experimental convective heat transfer coefficients and mass transfer coefficients of urban surfaces' の研究トピックを掘り下げます。これらはともに一意のフィンガープリントを構成します。

  • これを引用