电气化铁路隧道微波除冰仿真研究

发布时间：2019-01-26 11:06

【摘要】：在冬季,由于气温较低,电气化铁路隧道顶端裂缝处容易形成隧道挂冰,随着水流不断流出,挂冰越来越长,与接触网的绝缘距离越来越短,对隧道供电安全构成极大威胁。因此,解决好隧道除冰问题对电气化铁路的安全运行有着非常重要的意义。本文基于当前人工除冰和设备除冰的不足,提出将微波加热技术应用于电气化铁路隧道除冰。该方法通过天线发射微波加热隧道裂缝渗水处的混凝土,使得渗水处温度上升,温升超过5℃,促使渗水区跨越-5℃到0℃这一水凝结成冰的温度区段,防止渗水凝结成冰,实现隧道除冰目的。主要的研究工作如下:首先,基于微波加热理论,简要阐述了隧道微波除冰的原理和优势。根据电磁场理论,推导出微波损耗功率方程,指出影响物料吸收微波能力的因素。结合电磁波在介质中的传播特性,推导出微波在混凝土中传播的波动方程。根据热力学定律,推导出热量在混凝土中传递的导热微分方程,并依据隧道除冰实际情况,给出热边界条件。其次,依据仿真假设条件和隧道实际情况,建立隧道微波除冰仿真模型,并分别对2.45GHz和5.8GHz时微波除冰模型的温度场分布进行仿真,分析其路径温度分布和参考点温度时间历程,对比两者之间的微波除冰效率。结果表明,相同条件下,5.8GHz的微波除冰效率是2.45GHz时的2.3倍。最后,研究了天线输入功率、隧道风速、混凝土含水量以及环境温度等不同因素对隧道微波除冰效率的影响。其中天线输入功率与隧道微波除冰效率成正比关系,隧道风速和环境温度主要影响混凝土表面与空气之间的对流传热,隧道微波除冰效率随风速的增加和环境温度降低而降低,且隧道风速的影响比环境温度大。混凝土含水量主要决定混凝土材料的介电常数和损耗角正切,其对隧道微波除冰效率的影响最大,混凝土含水量越高,微波除冰效率越高。
[Abstract]:In winter, because of the low temperature, the tunnel ice is easily formed at the crack at the top of the electrified railway tunnel. With the water flowing out, the ice hanging becomes longer and longer, and the insulation distance from the catenary becomes shorter and shorter, which poses a great threat to the safety of the tunnel power supply. Therefore, it is very important to solve the deicing problem of tunnel for the safe operation of electrified railway. Based on the shortage of artificial deicing and deicing equipment, microwave heating technology is applied to deicing of electrified railway tunnel. In this method, the temperature of the seepage area is increased by microwave heating of concrete at the crack seepage place of the tunnel through antenna, and the temperature rise is more than 5 鈩，

本文编号：2415415