Mohd Hisyam Rasidi

テラスハウス周辺の緑被率と周辺気温低減効果に関する定量的把握:東南アジア・蒸暑気候地域における環境配慮型住宅地デザイン手法に関する研究 (その2)

The aim of this study is to investigate environmental situation surrounding terraced houses with greenery patterns, and to accumulate objective data and features in the new developed residential area in Malaysia. A computer microclimate simulation technique is applied by combining stored digital spatial data on GIS as main tools. As a results, i) There is almost no temperature changes between the current building shape and after changing the building aspect ratio without additional greening. However after green space added, some contributions for reducing surrounding temperature can be observed. ii) The relatively higher cooling effects of greenery in the surrounding building and block can be observed in the afternoon and evening. iii) Increasing approximately 11% green coverage ratio make effects of reducing about 0.5°C above the green spaces and about 0.3°C on the surrounding area.

Effect of the position of the visible sky in determining the sky view factor on micrometeorological and human thermal comfort conditions in urban street canyons

Poor daytime and night-time micrometeorological conditions are issues that influence the quality of environmental conditions and can undermine a comfortable human lifestyle. The sky view factor (SVF) is one of the essential physical parameters used to assess the micrometeorological conditions and thermal comfort levels within city streets. The position of the visible sky relative to the path of the sun, in the cardinal and ordinal directions, has not been widely discerned as a parameter that could have an impact on the micrometeorological conditions of urban streets. To investigate this parameter, different urban streets that have a similar SVF value but diverse positions of visible sky were proposed in different street directions intersecting with the path of the sun, namely N–S, NE–SW and NW–SE. The effects of daytime and night-time micrometeorological variables and human thermal comfort variables on the street were investigated by applying ENVI-met V3.1 Beta software. The results show that the position of the visible sky has a greater influence on the street’s meteorological and human thermal comfort conditions than the SVF value. It has the ability to maximise or minimise the mean radiation temperature (Tmrt, °C) and the physiological equivalent temperature (PET, °C) at street level. However, the visible sky positioned to the zenith in a NE–SW or N–S street direction and to the SW of a NW–SE street direction achieves the best daytime micrometeorological and thermal comfort conditions. Alternatively, the visible sky positioned to the NE for a NW–SE street direction, to the NW and the zenith for a NE–SW street direction and to the zenith for a N–S street direction reduces the night-time air temperature (Ta, °C). Therefore, SVF and the position of the visible sky relative to the sun’s trajectory, in the cardinal and ordinal directions, must be considered during urban street planning to better understand the resultant micrometeorological and human thermal comfort conditions.