脉动热管换热器传热性能及工程应用技术研究
发布时间：2018-08-03 15:56
【摘要】：随着工业科技的发展,相关行业及工业领域热设备工作的安全性及效率提高会面临很多新问题。一方面,随着集成度的提高,电子元器件尺寸越来越小,导致单位面积热负荷越来越高,使得传统散热方式很难满足要求;另一方面,随着节能压力的加大,低温余热回收的温差越来越小,使得传统换热设备很难达到目的。因此,传热过程的强化以及新型高效换热设备,越来越受到关注。脉动热管具有体积小、传热性能优良等特点。本文针对脉动热管的传热性能,通过对脉动热管可视化实验观测、气-液脉动热管换热装置传热性能实验研究,进而设计和开发了气-液脉动热管换热器。可视化实验观测方面:通过搭建可视化实验台,观测不同充液率脉动热管的流向、流型以及气泡的生长和消失过程,进而分析其传热性能。结论如下:(1)充液率影响脉动热管的正常启动及运行。充液率为87.3%的脉动热管所需启动温度较高,振荡幅度稳定但是较为缓弱;充液率为19.7%的脉动热管所需启动温度较低,虽能正常启动,但因充液率过低,难以形成循环,不利于热量传输;充液率为60.2%的脉动热管启动温度在两者之间,但振荡幅度最剧烈。从振荡幅度和启动温度来看,更优于充液率为47.5%的脉动热管。(2)从流型上来看,当脉动热管加热温度较低时,管内以塞状流为主;当脉动热管达到相应温度时,塞状流会过渡到环状流,管内会以环状流为主。传热性能实验研究方面:设计了由20根“U”形翅片管组成的气-液脉动热管换热实验装置,并搭建了实验台,对其传热性能进行了实验研究。结论如下:(1)热源温度对脉动热管工作性能影响较大。热源温度为45℃时开始启动,温度在60℃到80℃之间达到最佳运行状态。(2)实验结果分析表明:气-液脉动热管换热实验装置的传热性能优良,当量导热系数远远大于铜管。脉动热管换热器设计方面:在气-液脉动热管换热装置传热性能实验研究基础上,设计和开发了由80根“U”形翅片管组成的气-液脉动热管换热器,并对其设计方法、设计思路、设计步骤以及相关问题进行了阐述。
[Abstract]:With the development of industrial technology, the safety and efficiency of thermal equipment in related industries and industrial fields will face many new problems. On the one hand, with the increase of integration, the dimensions of electronic components become smaller and smaller, resulting in a higher heat load per unit area, which makes the traditional heat dissipation difficult to meet the requirements; on the other hand, with the increase of energy saving pressure, The temperature difference of low-temperature waste heat recovery is getting smaller and smaller, which makes the traditional heat exchanger difficult to achieve the purpose. Therefore, more and more attention has been paid to the enhancement of heat transfer process and new efficient heat transfer equipment. Pulsating heat pipe has the advantages of small volume and excellent heat transfer performance. In this paper, according to the heat transfer performance of pulsating heat pipe, the heat transfer performance of gas-liquid pulsating heat pipe heat exchanger is studied by visual experimental observation of pulsating heat pipe, and the gas-liquid pulsating heat pipe heat exchanger is designed and developed. Visual experimental observation: the flow direction, flow pattern, bubble growth and disappearance process of different liquid filling rate pulsating heat pipe were observed by building a visual experimental platform, and its heat transfer performance was analyzed. The conclusions are as follows: (1) the liquid filling rate affects the normal start-up and operation of the pulsating heat pipe. A pulsating heat pipe with a liquid filling rate of 87.3% requires a higher starting temperature, a stable oscillation amplitude but a relatively weak oscillation, and a low starting temperature for a pulse heat pipe with a liquid filling rate of 19.7%, although it can start normally, but it is difficult to form a cycle because of the low liquid filling rate. The starting temperature of the pulsating heat pipe with a liquid filling rate of 60.2% is between the two, but the amplitude of oscillation is the most intense. In terms of oscillation amplitude and starting temperature, it is better than the pulsating heat pipe with liquid filling rate of 47.5%. (2) from the flow pattern, when the heating temperature of the pulsating heat pipe is low, the plug flow is dominant in the tube, and when the pulsating heat pipe reaches the corresponding temperature, The plug flow will transition to the annular flow, and the annular flow will be dominant in the tube. Experimental research on heat transfer performance: an experimental apparatus of gas-liquid pulsating heat transfer pipe composed of 20 "U" finned tubes was designed, and an experimental bench was set up to study its heat transfer performance. The conclusions are as follows: (1) the temperature of heat source has great influence on the working performance of pulsating heat pipe. When the heat source temperature is 45 鈩，
本文编号：2162238
[Abstract]:With the development of industrial technology, the safety and efficiency of thermal equipment in related industries and industrial fields will face many new problems. On the one hand, with the increase of integration, the dimensions of electronic components become smaller and smaller, resulting in a higher heat load per unit area, which makes the traditional heat dissipation difficult to meet the requirements; on the other hand, with the increase of energy saving pressure, The temperature difference of low-temperature waste heat recovery is getting smaller and smaller, which makes the traditional heat exchanger difficult to achieve the purpose. Therefore, more and more attention has been paid to the enhancement of heat transfer process and new efficient heat transfer equipment. Pulsating heat pipe has the advantages of small volume and excellent heat transfer performance. In this paper, according to the heat transfer performance of pulsating heat pipe, the heat transfer performance of gas-liquid pulsating heat pipe heat exchanger is studied by visual experimental observation of pulsating heat pipe, and the gas-liquid pulsating heat pipe heat exchanger is designed and developed. Visual experimental observation: the flow direction, flow pattern, bubble growth and disappearance process of different liquid filling rate pulsating heat pipe were observed by building a visual experimental platform, and its heat transfer performance was analyzed. The conclusions are as follows: (1) the liquid filling rate affects the normal start-up and operation of the pulsating heat pipe. A pulsating heat pipe with a liquid filling rate of 87.3% requires a higher starting temperature, a stable oscillation amplitude but a relatively weak oscillation, and a low starting temperature for a pulse heat pipe with a liquid filling rate of 19.7%, although it can start normally, but it is difficult to form a cycle because of the low liquid filling rate. The starting temperature of the pulsating heat pipe with a liquid filling rate of 60.2% is between the two, but the amplitude of oscillation is the most intense. In terms of oscillation amplitude and starting temperature, it is better than the pulsating heat pipe with liquid filling rate of 47.5%. (2) from the flow pattern, when the heating temperature of the pulsating heat pipe is low, the plug flow is dominant in the tube, and when the pulsating heat pipe reaches the corresponding temperature, The plug flow will transition to the annular flow, and the annular flow will be dominant in the tube. Experimental research on heat transfer performance: an experimental apparatus of gas-liquid pulsating heat transfer pipe composed of 20 "U" finned tubes was designed, and an experimental bench was set up to study its heat transfer performance. The conclusions are as follows: (1) the temperature of heat source has great influence on the working performance of pulsating heat pipe. When the heat source temperature is 45 鈩，
本文编号：2162238
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