surface temperature

The purpose of this study is to develop a thermal design tool for architectural designer by combining a heat balance simulation for urban surfaces, including buildings, the ground and greenery, with a 3D-CAD. This tool is constructed by improving the previous simulation model, which uses the Geographic Information System for the input data. The simulation algorithm is improved so as to predict the surface temperature distribution of urban blocks while taking into account the actual design of the outdoor space using the 3D-CAD system.

This study assesses the extent of the cooling effects of waterways on the thermal environment of urban districts of Osaka by measurement and simulation. The thermal environments of districts with and without waterways were measured in summer. The effects of the change of configuration of the district near waterway were calculated using computer fluid dynamics simulation. Results show the following. 1) Measured daily mean air temperatures were 0.5–0.8 K lower and SET* was 1.4–2.9 K lower in the district with the waterway than those in the district without waterways in peak summer.

The materials that are used in outdoor spaces are of prime importance as they modulate the air temperature of the lowest layers of the urban canopy layer, they are central to the energy balance of the surface and they form the energy exchanges that affect the comfort conditions of city people. Paved surfaces contribute to sunlight’s heating of the air near the surface. Their ability to absorb, store and emit radiant energy has a substantial affect on urban microclimate.  

There is a need to improve the accuracy of infrared thermography for measuring the temperature distribution of building exterior surfaces. Thermography is useful for building ventilation and thermal analysis, as well as understanding city ventilation and the urban heat island phenomenon. The key in correcting infrared images is to quantify accurately the reflected infrared contribution of surrounding surfaces as well as that of the atmosphere. Two new methods are proposed here for correcting measured temperature distribution of building exterior surfaces by infrared thermography.

The authors' previous analysis of dynamic insulation is extended to include the inner and outer air film resistances with the objective of modelling the variation in surface temperature with air flow. The boundary condition that comes closest to predicting the variation of the surface temperature with air flow is one which assumes that the conduction heat flux at the wall surface, rather than the net heat flux, is equal to the flux incident on the wall from global environmental temperature, T.;.