Watering on porous pavement for improvement of environmental human thermal comfort in an ecological community in arid area: A case study in Lanzhou, China

Abstract

• A method of watering on porous pavement for improvement of thermal comfort is proposed. • Universal thermal climate index for thermal comfort evaluation is introduced. • A complex correlation coefficient with relationship between UTCI and environmental parameter is studied. A method of watering on porous pavement was put forward to improve environmental thermal comfort of human body in an ecological community arid area in Lanzhou, China. A mathematic-physical coupling model was established based on water evaporation of porous pavement. Universal thermal climate index (UTCI) was introduced to evaluate environmental thermal comfort level. Multiple linear regression analysis between meteorological factors and UTCI was conducted. A complex correlation coefficient was calculated to study relation between UTCI and each environmental parameter. Variation of environmental parameters under water evaporation on porous pavement and ordinary pavement were also compared. Watering interval based on environmental parameters for porous pavement was studied. Results show that UTCI will be in range of human thermal comfort when relative humidity reaches more than 65% under air temperature of 16 °C. Relative humidity becomes more and more sensitive to thermal comfort when air temperature is less than 20 °C. While the thermal discomfort of human body gradually increased with the increase in relative humidity when air temperature is higher than 26 °C. When air temperature is around 20 °C, watering measure should be taken. Amount of watering in a single time should meet the requirement of water evaporation for 1.67 h under local climatic weather conditions. Watering interval should be the sum of evaporation time of a single watering, and time period required for UTCI within comfortable range. Regularly watering on porous pavement can significantly improve environmental human thermal comfort in ecological community in arid areas.