隧道热害环境下电力机车蓄冷式冷却塔散热性能研究

Heat dissipation performance study of electric locomotive storagecooling tower under tunnel heat damage environment

针对西部某铁路所处的高原隧道热害环境,提出一种电力机车蓄冷式冷却塔结构及其运行方案,通过对蓄冷及释冷过程进行仿真,分析换热器的冷却性能并对其结构进行优化。研究结果表明:当换热器蓄冷运行时,相对于壳体两侧无翅片结构,采用壳体空气侧加翅片和壳体双侧加翅片,相变蓄冷时间从113 min分别缩短至80 min和47 min;当换热器释冷运行时,乙二醇水溶液经相变蓄冷换热器冷却,传热管道添加间距为8 mm的翅片,有效冷却时间(冷却介质出口温度低于55℃)从无翅片结构的1.5 min延长至16 min,超过设计要求的14 min,有效解决了机车冷却塔的散热难题。

Inview of the heat damage environment in plateau tunnels along a railway in western China,a phase change cold storage cooling tower and its operation scheme for electric locomotive were proposed.Cold-storage and cold-release processes of this cooling tower were simulated,its cooling performance was analyzed and the structure of the heat exchanger was optimized.The results show that when the heat exchanger is running for cold storage, compared with the finless structure, the phase change cold-storage time of the structure with fins on the airside and the structure with fins on the both sides of the shell is shortened from 113 min to 80 min and 47 min,respectively. When the heat exchanger is running for cold-release, the cooling medium (ethylene glycol aqueoussolution) is cooled by the phase change cold storage heat exchanger and the effective cooling time (while the outlettemperature of the cooling medium is less than 55 ℃) of the structure with 8 mm spacing fins on the heat transferpipeline is extended from 1.5 min(for the finless structure) to 16 min, exceeding the designed requirements(14min),which solves the heat dissipation problem of locomotive cooling tower.