Abstract
A free convection enhanced by a heating plate is studied in air-chambers under laminar conditions. Observations show the influence of the plate shape. Among the different convection patterns, a stationary cell is clearly identified. This bell-shaped convection typically represents the pollution domes observed over many cities. Convection begins immediately a horizontal temperature difference is created. From this point of view, a heat island situation appears quite different from a Rayleigh-Bénard one. Experiments reveal that the ambient stratification affects the Nusselt-Rayleigh relationship. The scale of the convection, the question of similarity and the limits of the experimental method are discussed. The results of experiments lead to the formulation of proposals concerning physical mechanisms which occur in the real atmosphere.
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Giovannoni, J.M. A laboratory analysis of free convection enhanced by a heat island in a calm and stratified environment. Boundary-Layer Meteorol 41, 9–26 (1987). https://doi.org/10.1007/BF00120428
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DOI: https://doi.org/10.1007/BF00120428