高温钠热管传热性能试验研究

为获得高温钠热管传热性能，开展真空条件下钠热管启动性能和等温性能试验，获得了钠热管真空条件下启动速度与等温性能数据；开展强制冷却工况条件下传热性能试验，获得了钠热管声速限特性与试验工况下的最大传热功率。经试验验证，所研制高温钠热管在真空条件下，580 ℃时完全启动，启动用时20 min，轴向壁面温差低于11 ℃，等温性能良好；钠热管传热功率在工作温度为500～650 ℃时受声速极限限制，在650 ℃以上受携带极限限制；在750 ℃和850 ℃时，测得热管最大散热功率分别为4.78 kW与8.02 kW，对应的最大轴向热流密度分别为1.51 kW/cm²与2.53 kW/cm²。试验结果表明，所研制钠热管具有较强传热能力，可满足热管式核反应堆等工程应用需求。

Experimental Study on Heat Transfer Performance of High Temperature Sodium Heat Pipe

In order to obtain the heat transfer performance of high temperature sodium heat pipe, the start-up performance and isothermal performance tests of sodium heat pipe under vacuum conditions were carried out, and the start-up speed and isothermal performance data of sodium heat pipe under vacuum conditions were obtained. Heat transfer performance tests under the forced cooling conditions were carried out, and the sonic limit characteristics of sodium heat pipe and the maximum heat transfer power under test conditions were obtained. The experimental results show that the developed high temperature sodium heat pipe is fully started at 580 ℃ under vacuum condition, and the start-up time is 20 minutes, the axial wall temperature difference is lower than 11 ℃, and the isothermal performance is good. The heat transfer power of sodium heat pipe is limited by the sonic limit in the temperature range of 500-650 ℃, and is limited by carrying limit in the operating temperature above 650 ℃. When the working temperature is 750 ℃ and 850 ℃, the measured maximum heat transfer power of the heat pipe is 4.78 kW and 8.02 kW, respectively, and the maximum axial heat flux density was 1.51 kW/cm² and 2.53 kW/cm², respectively. The test results show that the developed sodium heat pipe has strong heat transfer capability which can meet the needs of heat pipe nuclear reactors and other engineering applications.