Proper evaluation of the external convective heat transfer for the thermal analysis of cool roofs

Cool materials are characterized by high solar reflectance and high thermal emittance; when applied to the external surface of a roof, they make it possible to limit the amount of solar irradiance absorbed by the roof, and to increase the rate of heat flux emitted by irradiation to the environment, especially during nighttime. However, a roof also releases heat by convection on its external surface; this mechanism is not negligible, and an incorrect evaluation of its entity might introduce significant inaccuracy in the assessment of the thermal performance of a cool roof, in terms of surface temperature and rate of heat flux transferred to the indoors. This issue is particularly relevant in numerical simulations, which are essential in the design stage, therefore it deserves adequate attention. In the present paper, a review of the most common algorithms used for the calculation of the convective heat transfer coefficient due to wind on horizontal building surfaces is presented. Then, with reference to a case study in Italy, the simulated results are compared to the outcomes of a measurement campaign. Hence, the most appropriate algorithms for the convective coefficient are identified, and the errors deriving by an incorrect selection of this coefficient are discussed.

Masked constituent priming of English compounds in native and nonnative speakers

The present research explores the degree of morphological structure of compound words in the native and nonnative lexicons, and provides additional data on the access to these representations. Native and nonnative speakers (L1 Spanish) of English were tested using a lexical decision task with masked priming of the compound’s constituents in isolation, including two orthographic conditions to control for a potential orthographic locus of effects. Both groups displayed reliable priming effects, unmediated by semantics, for the morphological but not the orthographic conditions as compared to an unrelated baseline. Results contribute further evidence of morphological structure in the lexicon of native speakers, and suggest that lexical representation and access in a second language are qualitatively comparable at relatively advanced levels of proficiency.