抄録
In this report, we observed the time lag in ignition when wood is exposed to the const. high temp. (500～800°C), and we also observed the effect to the time lag of the factors such as heated area, heated temp., thickness of board, water contained, roughness of surface, oldness, etc. The following results were obtained :
(1) The time lag is increased rapidly with the decrease of temp. as shown in the following formula.
log τ =(A/Ⓗ)+B
τ : time lag.
Ⓗ : heated temp. (°K)
A, B : const.
(2) The time lag is increased linearly with the increase of water volume contained in wood.
(3) The thickness of the board and heated area have no connection in the time lag excepting both are very small.
(4) Oldness of boards, roughness of the surface, etc. have almost no relation on the time lag.
(5) The time lag in ignition of hard wood is larger than that of soft wood.
