变压器油池火燃烧规律的实验研究*

为对变压器油池火灾进行准确有效的灭火，研究不同尺寸和不同厚度下变压器油的火灾动力学特征和基本燃烧特性，具体分析变压器油的燃烧过程和变压器油燃烧速率、火焰温度以及辐射热流随油池直径以及厚度的变化规律。结果表明:整个油品的燃烧过程分为预热燃烧阶段、稳定燃烧阶段和火焰熄灭阶段。对于厚度大于10 mm的油池燃烧，稳定阶段的燃烧速率与油层厚度无关，稳定阶段的燃烧速率随着油池直径的增加而增加。同时，变压器油火灾连续火焰区温度接近750 ℃。对于稳定燃烧阶段下的变压器油燃烧，基于辐射通量可得出在燃烧过程中，辐射热量占总燃烧热的占比约为1/3。研究结果可丰富变压器油燃烧的基础数据，为变压器火灾的灭火提供参考。

Experimental study on combustion laws of transformer oil pool fire

The transformer oil is a common coolant for the electric power devices due to its perfect insulation,strong thermal conductivity and large specific heat capacity,but the transformer oil is a flammable substance which is prone to ignite during the use.In order to extinguish the actual transformer oil fire accurately and effectively,the fire dynamics characteristics and basic combustion characteristics of transformer oil under different sizes and different thicknesses were studied,then the combustion process of transformer oil and the change laws of combustion rate,flame height and radiant heat flux of transformer oil with the diameter and thickness of oil pool were analyzed.The results showed that the whole combustion process of oil could be divided into three stages,including the ignition stage,steady combustion stage and flame extinction stage.For the combustion of oil pool with the thickness of more than 10 mm,the combustion rate in the steady combustion stage was independent on the thickness of oil layer,while it increased with the increase of oil pool diameter.Meanwhile,the temperature in the continuous flame zone of transformer oil pool fire was close to 750 ℃.For the combustion of transformer oil in the steady combustion stage,the ratio of radiation heat to the total combustion heat was about 1/3 according the radiation flux in the combustion process.The results can enrich the basic data for the combustion of transformer oil,and provide reference for the extinguishing of transformer fire.