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.
1 September 2019 in Case Studies in Thermal Engineering
To achieve carbon neutrality in 2060 (China), building energy-saving has been highly concerned. University buildings have great energy-saving potential as part of energy consumption where 70% of energy loss is caused by heat transfer from the envelope. However, most of the research on energy-saving factors for envelopes is limited to a certain climate or a specific building type, and the optimal configuration of envelopes under different climatic regions has not been well solved. Therefore, the influence degree and appropriate parameters of each factor of the teaching-office building envelopes on energy consumption under different climates were analyzed in this paper by orthogonal design and numerical simulation. Results show that: (1) Solar heat gain coefficient (SHGC) and indoor air change rates (ACH) [the heat transfer coefficient of the exterior wall (Kwall) and ACH] are the main factors affecting the cooling [heating] load, the insulation form of the exterior wall (Wins) and Kwall [Wins and solar radiation absorption coefficient of exterior surface materials (ρs)] have less influence; (2) The important ranking and optimal level of the influence of each factor on the cooling (or heating) loads are related to local load demands; (3) For the annual load, Kwall and the heat transfer coefficient of the exterior window (Kwin) is the focus of energy-saving in severe cold and cold zones, but their impact is not significant in Guangzhou and Kunming, and the high significance of SHGC is only shown in Hohhot, Lhasa, Guangzhou, and Haikou; (4) The annual load energy savings reach 39.64%–57.57% in different climates by optimizing all factors. The research results can provide directions and data references for the energy-saving design and renovation of educational building envelopes in different climates (China).