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This paper aims to study various spatial functional layouts and test how these different design approaches affect pedestrian comfort under shell structures. The considered shell shape was developed aiming an efficient distribution of loads allowing prefabrication with ultra-thin concrete elements. As shell structures can define semi-exterior spaces and assume open locations within some urban contexts, the study of how different design strategies for the underlying space affect user's comfort is of upmost importance. Several wind tunnel tests were performed on a triangular thin shell scale model with a few different spatial user's area layouts allowing to understand to which extent some design decisions compromise pedestrian wind comfort. The experimental campaign follows an iterative process leading to conclusions that can guide future projects and contribute to a multidisciplinary and transversal understanding of these innovative structures. • Wind tunnel tests for pedestrian comfort assessment under free form concrete shells. • Study of pedestrian comfort's influence on space occupation for semi-exterior spaces. • Integrated design solutions for functional and comfort needs. • Most critical areas under the shell's legs, depending greatly on each design solution and wind incidence. [ABSTRACT FROM AUTHOR]

One of the most important concerns when designing buildings as liveable spaces is the indoor comfort. This depends on different factors, including daylight availability and discomfort glare conditions. The increasing use of glazing areas in the building's envelopes can lead to high energy consumption and problems such as visual discomfort. The use of shading devices stands out as a sustainable design strategy to reduce energy consumption in the buildings. This work presents an experimental analysis of the impact of an innovative shading device, a double-tilted venetian blind (DTVB) with different positions of upper and lower slats, on the indoor daylight conditions. Moreover, discomfort glare evaluation, through DGPs metric, is performed. The experimental campaign was conducted in an outdoor test cell during three periods of the year: summer solstice, winter solstice and autumn equinox. Experiments were carried out with both white and grey DTVBs, for several positions of upper and lower slats, under clear and overcast sky conditions. This comprises the measurement of indoor and outdoor horizontal and vertical illuminances and irradiances and solar and visible transmittance of the fenestration. It was concluded that DTVBs can achieve a higher performance, regarding solar protection, daylighting and glare control, when compared with more traditional venetian blinds systems. • Experimental daylight performance study of an innovative shading device. • A double tilted venetian blind (DTVB) with different slats angles was studied. • Daylighting parameters were measured in a test cell. • White and grey DTVB slats were evaluated under clear and overcast sky conditions. • DTVB have higher daylight efficiency than traditional Venetian blinds. [ABSTRACT FROM AUTHOR]

An accurate assessment of the airflow in naturally ventilated double skin facades (DSF) is crucial for a correct design and performance evaluation. Measuring and predicting DSF airflow is not a straightforward task, given the stochastic nature of the wind, which can assist or oppose the buoyancy force. The present paper resumes the results of airflow measurements inside a naturally ventilated double skin facade using a tracer gas technique. The tests were performed on an outdoor air curtain (OAC) DSF test cell with a movable slat venetian blind. Measurements with no active shading and at night were also performed. Outdoor and test cell air gap temperatures were continuously measured and wind pressure coefficients were determined from wind tunnel tests. Experimental results were then compared to those obtained by a simple model taking into account both thermal and wind effects on the facade. From this comparison discharge coefficients were estimated, which can be used for characterizing the DSF behaviour. [ABSTRACT FROM AUTHOR]

Abstract: The increasing use of glazed areas in the building envelope can lead to high solar gains and glare problems that can strongly impact the entire building energy consumption, peak loads and indoor comfort. An important and fundamental strategy in sustainable building design for controlling solar heat gains and daylighting through fenestration is the use of shading devices. Therefore, it is recommended to use detailed models that can accurately estimate the optical properties of the different types of shading devices (such as roller blinds and venetian blinds) and include their effects in the glazing system analysis. This paper describes a net radiation method for determining both solar and visible optical properties of glazing with shading devices, particularly venetian blinds. Some numerical results were compared with in situ experimental measurements carried out in an outdoor test cell. The experimental work included the measurement of illuminance and irradiance fluxes and the determination of the visible and solar transmission properties of the fenestration system. The agreement between numerical predictions and experimental results was better for overcast than clear sky conditions. Moreover, a venetian blind control strategy that blocks direct solar radiation, whilst enabling the transmission of diffuse radiation to indoors, is implemented. [Copyright &y& Elsevier]