The cooling effect of the river and the canal on the micro-climate in urban area

To evaluate the effect of river and canal on thermal environment, we performed the field observation at the Tama River and the Shibuura Canal. The detailed measurement of vertical temperature distribution within the river and the canal and measurement of urban temperature along the street crossing the river and the canal were carried out and horizontal extent of cooling effect were confirmed by these observation. In the Tama River, the cooling effect is restricted in day time, while in the Shibuura Canal, this cooling effect appeared in night time

Experimental investigation of flow in embayment

This study reports the results of flow visualization and velocity measurements in embayment. Flow visualization was done using aluminum powder as tracer and velocity measurements were carried out with electromagnetic velocitymeter. Visualized flow shows the formation of large organized eddies at the embayment-main channel interface and the existence of primary recirculation, secondary recirculation and flow separation. Measured velocity reveals that the mean velocities vary little with depth for low flow condition. Flow becomes more complex for flood flow condition and then, depth averaging is meaningless

Field observation on thermal environment around Turumi river and in the Tama river

Field observation was carried out around the Turumi river and in the Tama river to estimate their cooling effect on the thermal environment in the surrounding area. The hourly measurement of air temperature distribution revealed that the affected zone by the Turumi river was restricted to the region close to the river course. The infrared thermal image sensor was applied to identify the correlation between the land cover and the surface temperature in the Tama river. It was found that at noon the surface temperature was the highest on revetment works, then pavements, playground and the lowest on grass field

Hydraulic characteristics of flows in man-made embayments

Flows in artificial embayments are investigated using flow visualization, two-component electromagnetic velocitymeter and thermal image processing technique. It is shown that large vortices develop along the embayment-main channel interface to exchange momentum and mass and that the shape of embayment and the type of structure installed along the interface exert considerable effect on the development of the vortices. Furthermore, time-averaged velocity distribution in embayment is found to vary little with depth