Abstract
Tokyo Metropolitan Fire Board made an experiment on the effect of the water spray method for the extinction of fire. We, research members of Building Research Institute, made use of this experiment, and measured the velocity and temperature of the fire flame when it was passing through the window of the burning house and its temperature after it passed the window. The important results obtained are as follows :
(1) In the window plane, the pressure difference between the inner and outer air increases linearly with the vertical distance from the neutral layer above which the inner pressure is larger than the outer, and so the stream velocity through the window increases quadratically with the height in the range above the neutral layer.
(2) The velocity distribution of that stream in the window plane is nearly similar to its temperature distribution.
(3) Above-mentioned similarity holds also between the velocity and temperature variation at any point in the window.
(4) The temperature decrease of the issued flame towards the down stream is just like that of the upward stream from the heat sources arranged on a circle or a circular heat source, already reported by S. Yokoi. The decrease is slight in a range near the window but it becomes remarkable from a certain distance and in this region the temperature is nearly inversely proportional to 5/3 power of the distance from the window.
