288 publications from this institution
Urban parks are an important component of urban public green space and a public place where a large number of urban residents choose to conduct outdoor activities. An important factor attracting people to visit and stay in urban parks is its outdoor thermal comfort, which is also an important criterion for evaluating the liability of the urban environment. In this study, through field meteorological monitoring and a questionnaire survey, outdoor thermal comfort of different types of landscape space in urban parks in Chengdu, China was studied in winter and summer. Result indicated that (1) different types of landscape spaces have different thermal comforts, (2) air temperature is the most important factor affecting outdoor thermal comfort; (3) because the thermal sensation judgment of outdoor thermal comfort research in Chengdu area, an ASHRAE seven-sites scale can be used; (4) the neutral temperature ranges of Physiological Equivalent Temperature (PET) and Universal Thermal Climate Index (UTCI) in Chengdu in winter and summer were obtained through research; (5) and UTCI is the best index for evaluating outdoor thermal comfort in Chengdu. These findings provide theoretical benchmarks and technical references for urban planners and landscape designers to optimize outdoor thermal comfort in urban areas to establish a more comfortable and healthy living environment for urban residents.
Under the fact that solar chimney was less investigated in multi-storey buildings, a theoretical model was then developed for solar chimney-induced buoyancy-driven natural ventilation. This is the first study addressing the influences of the storey number on ventilation rates for multi-storey solar chimney (SC) buildings. A storey correction coefficient was proposed to predict the SC-induced ventilation at various floors with identical air inlet areas. The theoretical model was established to elucidate the relationship among ventilation flow rates, solar radiation intensity, vent sizes and storey number (f), where the numerical results have also been validated. Although the total SC ventilation performance is enhanced, its enhancement with a higher chimney cavity was less effective when compared to those solar chimneys in single-storey buildings. This is due to the higher chimney cavity hindering the ventilation performance of the lower floors. The volume flow rate decreased exponentially for the top floors of each building when the two-storey building increased to a seven-storey building. For buildings with more than three storeys, the overall volume flow rate was more sensitive to the cavity gap than the solar radiation intensity, with an improvement in ventilation by 45.6% compared to 26.0% under the same conditions, respectively. To maximize the total flow rate, the optimal cavity gap should increase gradually from 0.2 m to 1.5 m for single-to seven-storey buildings. The findings of this study contribute to a further application of solar chimneys in multi-storey buildings.
