激光清除树障温度和效率影响因素分析

Analysis of Factors Affecting Temperature and Efficiency in Laser Clearing Tree Barriers

高能激光清除输电线路通道树障过程中,激光能量过高可能导致火势过大,继而引发火灾。为了分析激光照射树障时的温度特性和效率规律,以6种典型树木类型为研究对象,建立烧蚀模型;随后对激光灼烧树障时温度和效率影响因素开展研究,针对激光功率、树木种类和风速等因素对树木灼烧的影响情况进行了仿真分析及激光灼烧试验。结果表明,清障效率随着激光功率的增加而增加。随着树木密度的增大,烧蚀厚度呈下降趋势,在密度范围为246~963 kg/m^(3)时,烧蚀厚度为110~430 nm,清除不同种类的树木所需时间的差距会达到4倍。随着风速的增加,激光灼烧树障时照射中心最高温度逐渐降低,在风速为0.3 m/s增加到3 m/s时,烧穿时间减少了6.42%~12.53%,风速对激光清除树障的效率有着轻微的提高作用。

In the high-energy laser removal of tree barriers on transmission line channels,excessive laser energy may lead to extreme fire and subsequent fire.To analyze the temperature characteristics and efficiency law when laser irradiates tree barriers,six typical tree types were used as research objects to establish the ablation model.Subsequently,the factors affecting the temperature and efficiency when laser burns tree barriers were studied.The simulation analysis was conducted for the influence of laser power,tree types,and wind speed on the tree burning situation.Finally,the laser burning tests were carried out.The results show that the clearing efficiency increases with laser power.With the increase in tree density,the ablation thickness tends to decrease.Within the density range of 246~963kg/m^(3),the ablation thickness is 110~430nm,and the difference in the time required to clear different kinds of trees will reach four times.With the increase of wind speed,the maximum temperature of the irradiation center when laser burns tree barriers gradually decreases,and the ablation penetration time decreases by 6.42%~12.53%when the wind speed increases from 0.3m/s to 3m/s.The wind speed has a slight improvement effect on the efficiency of laser tree barrier removal.