摘要
以红棕木粉为实验材料,利用自制堆积粉尘阴燃实验装置,研究了以高温热球为例的非恒温热源的初始温度、尺寸等火源特性参数对木粉尘堆内不同区域阴燃着火特性的影响规律。实验结果表明:木粉的平均阴燃着火速度低于阴燃稳定传播速度,且距粉堆外表面越近阴燃传播速度越快;木粉阴燃着火速度随热源尺寸的增加而增加,但在较小差异尺寸下则出现不符规律的矛盾点;非恒温热源初始温度对木粉阴燃着火速度的影响和热源尺寸影响相似,但在一定温度范围内影响不大。实验结果充分说明及验证了理论分析和预测的正确性。
The red brown wood dust as the experimental material, using the self-made experimental device of dust smoldering, studying the influence law of ignition characteristics of different area in wood dust heap with high temperature steel balls with different initial temperatures and sizes. The experimental results show that the average velocity of smoldering fire of wood dust is lower than the steady propagation velocity,and from the outer surface of the heap near the smoldering faster;The smoldering ignition velocity of wood dust increased with the increase of heat source size, but in the smaller difference size appear inconsistent contradiction point; The effect of smoldering ignition velocity with the initial temperature of non-isothermal heat source is similar to the size, but in a certain temperature range has little effect. The experimental results fully illustrate and verify the correctness of the theoretical analysis and prediction.
引文
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