单线内螺纹重力热管强化换热实验研究
发布时间：2018-07-15 18:22
【摘要】：热管作为高效的传热元件,在工程应用、科学研究和能源开发等领域已取得广泛应用。近年来随着国家对能耗问题越来越关注,强化热管换热性能成为热管技术研究的重要内容之一。本文通过查阅参考文献,了解国内外强化热管换热技术研究现状,将其分为变化热源供应方式、对管壳内壁做处理和改善管内组件及工质三类。为探究对管壳内壁做处理这种技术强化重力热管换热的效果,采取在内壁布置单线内螺纹的方法,制取了不同分布单线内螺纹的重力热管和光滑重力热管。通过分析重力热管传热模型和基本理论,计算相关传热极限,探讨了热管传热过程及内螺纹结构强化换热的机理。搭建了相应的实验台,详述了实验系统,给出了实验数据处理方法,并对其进行误差分析。实验对比光滑重力热管和内壁全部布置单线内螺纹重力热管的传热特性发现,内螺纹重力热管的启动特性优于光滑重力热管。不同加热条件下,内螺纹结构使得重力热管换热得到强化,提高了传输功率,增大了等效对流换热系数,减小了总热阻。两种重力热管在小倾角放置时,随着温度的升高对等效对流换热系数的提高效果不如大倾角明显。同一油浴温度为150℃时,最佳倾角为75°。实验研究单线内螺纹分布对热管强化换热的影响发现,在同一油浴温度下,各单线内螺纹分布不同的重力热管的启动特性都要优于光滑重力热管,且全螺纹重力热管最优。在不同油浴温度下,布置内螺纹能够有效地降低热管的工作温度。计算对流换热系数发现,实验选型的内螺纹布置在绝热段和冷凝段强化效果最优。针对实验中蒸发段布置内螺纹强化换热效果不好的原因,本文从两方面分析,即螺纹强化因子和充液率,得出主要影响因素是充液率。
[Abstract]:As an efficient heat transfer element, heat pipe has been widely used in engineering applications, scientific research and energy development. In recent years, as more and more attention has been paid to energy consumption, enhancing the heat transfer performance of heat pipe has become one of the important contents of heat pipe technology research. In this paper, the current research situation of heat transfer technology of enhanced heat pipe at home and abroad is understood by consulting references, which is divided into three categories: changing heat source supply mode, treating the inner wall of tube and shell and improving tube inner assembly and working fluid. In order to explore the effect of heat transfer enhancement on the inner wall of tube and shell by using this technique, the gravity heat pipe and smooth gravity heat pipe with different distribution of single line internal thread were made by placing single line internal thread in the inner wall. Based on the analysis of heat transfer model and basic theory of gravity heat pipe, the heat transfer limit is calculated, and the mechanism of heat transfer enhancement by heat pipe heat transfer process and internal screw structure is discussed. The corresponding experimental platform is built, the experimental system is detailed, the experimental data processing method is given, and the error analysis is carried out. Compared with the heat transfer characteristics of the smooth gravity heat pipe and the single line internal threaded gravity heat pipe, it is found that the starting characteristic of the inner thread gravity heat pipe is better than that of the smooth gravity heat pipe. Under different heating conditions, the heat transfer of gravity heat pipe is strengthened by internal screw structure, the transmission power is increased, the equivalent convection heat transfer coefficient is increased, and the total thermal resistance is reduced. When the two kinds of gravity heat pipes are placed at small inclination angle, the effect of increasing the equivalent convection heat transfer coefficient with the increase of temperature is less obvious than that of large inclination angle. The optimum inclination angle is 75 掳when the same oil bath temperature is 150 鈩，
本文编号：2124986
[Abstract]:As an efficient heat transfer element, heat pipe has been widely used in engineering applications, scientific research and energy development. In recent years, as more and more attention has been paid to energy consumption, enhancing the heat transfer performance of heat pipe has become one of the important contents of heat pipe technology research. In this paper, the current research situation of heat transfer technology of enhanced heat pipe at home and abroad is understood by consulting references, which is divided into three categories: changing heat source supply mode, treating the inner wall of tube and shell and improving tube inner assembly and working fluid. In order to explore the effect of heat transfer enhancement on the inner wall of tube and shell by using this technique, the gravity heat pipe and smooth gravity heat pipe with different distribution of single line internal thread were made by placing single line internal thread in the inner wall. Based on the analysis of heat transfer model and basic theory of gravity heat pipe, the heat transfer limit is calculated, and the mechanism of heat transfer enhancement by heat pipe heat transfer process and internal screw structure is discussed. The corresponding experimental platform is built, the experimental system is detailed, the experimental data processing method is given, and the error analysis is carried out. Compared with the heat transfer characteristics of the smooth gravity heat pipe and the single line internal threaded gravity heat pipe, it is found that the starting characteristic of the inner thread gravity heat pipe is better than that of the smooth gravity heat pipe. Under different heating conditions, the heat transfer of gravity heat pipe is strengthened by internal screw structure, the transmission power is increased, the equivalent convection heat transfer coefficient is increased, and the total thermal resistance is reduced. When the two kinds of gravity heat pipes are placed at small inclination angle, the effect of increasing the equivalent convection heat transfer coefficient with the increase of temperature is less obvious than that of large inclination angle. The optimum inclination angle is 75 掳when the same oil bath temperature is 150 鈩，
本文编号：2124986
本文链接：https://www.wllwen.com/kejilunwen/dongligc/2124986.html
