摘要
通信基站是通信系统的重要组成部分,其内部温湿度和洁净度等环境参数不仅直接影响着通信设备的可靠运行和使用寿命,更关系到通信的顺畅与安全。通信基站内设备散热量大且集中,基站内部设备全年不间断高负荷运行,即使在冬季也可能存在散热情况,因此承担散热负荷的空调必须连续不断的高负荷运行,从而导致了通信基站高额的电费支出。
因此在目前能源状况较为紧张的形势下,能源的有效利用和节能成为通信站设计中必须考虑的问题之一。作为通信基站空调节能的替代品——空气换热器就是在这样的背景下产生的。该设备的节能原理是在室外温度较低时,利用室内外空气的温差传热,消除基站机房内的余热量,在过渡季或冬季部分替代或完全替代基站机房内的空调设备,实现通信基站的空调节能。
本文主要从以下三个方面进行研究:
(1)通信基站用隔离板式空气换热器的实验研究。
对开发研制的板式换热器的传热性能以及压力降与风量以及温差的关系进行实验研究,并对该换热器的实际降温效果进行测试。结果表明,该换热器的换热系数和压降均随着风量的加大而增大,且变化趋势较陡;而换热效率随着风量的增大而减小,但是变化趋势较平缓。
(2)新型重力热管换热器的研究。
分析了通信基站用热管换热器的特点,用常规计算法设计一种适用于通信基站的重力式热管换热器,用VB语言编译一个通信基站用重力式热管换热器的设计计算程序,并对其计算过程和模拟计算结果进行分析。
(3)板式换热器与热管换热器应用于通信基站的全国经济适用性分析与比较。
空气换热器的使用受到室内外温差的限制,且板式换热器和热管换热器的性能是不同的,这两种换热器在全国范围内的经济性如何直接影响到其适用性。用DEST软件计算了全国五个气候区主要城市的典型基站的全年逐时冷负荷,并对各个地区应用两种空气换热器进行节能分析,结果表明,通信基站用空气换热器节能效果是非常显著的,年节电率最高的是昆明(温暖地区),高达39%(板式换热器),广州(夏热冬暖地区)最差,约14%(板式换热器);板式换热器和热管换热器的节能效果相当。
Communication base station is an important part of the communication system. Its internal temperature, humidity, degree of cleanliness and other environmental parameters not only have a direct impact on the communication equipment's reliability and service life, but also relate to the smooth operation and security of the communication process.
Communication base station's heat dissipating capacity is big and concentrated. Its internal equipment operates uninterrupted all the year with a high loading, even in the winter, there may be heat dissipating, so the air-conditioning which bears the heat dissipating capacity needs to working continuously with a high loading, thus entaking a high electricity cost on the communication base station.
So under the current tense energy circumstance, effectively energy-using and energy-saving are necessary in the design of the communication base station. Under this background, there is the energy saving alternatives of base station's air conditioning systems—air heat exchanger. The principle of energy saving of this equipment as follows: in intermediate season and winter, when the outdoor temperature is low, using the indoor and outdoor air temperature heat transferring to eliminate communication equipment plant's excess heat so as to substitute the air-conditioning, then realizing communication base station's energy saving.
The dissertation can be divided into three parts:
(1) The experimental study on the isolated plate air heat exchanger used in communication base station. The aim of experiment is to find the relationship between the heat transfer performance and air velocity, and to find the relationship between the pressure drop and air velocity. The cooling effects of the heat exchanger will also be studied. The results show that the heat transfer coefficient and pressure drop increase as the air velocity increases, and the change is in tends in steep. And the heat transfer efficiency decreases as the air velocity increases, but the trend is gentle.
(2) The study on gravity heat pipe heat exchanger.
According to the features of the communication base station, a gravity heat pipe exchanger has been designed using conventional calculation, and based on VB, the design and calculation is made. In addition, the calculation process is introduced by a project example, and its computation results are studied.
(3) The applicability analysis on the two types of heat exchanger used in communication base station all over china.
Whether the heat exchanger use or not is determined by the difference between indoor and outdoor air. And the performance of two types of heat exchanger is different. How about the economy of two types of heat exchanger in the national? And that result will directly affect the application in the national. The yearly load of a typical base station is calculated by DEST, and the calculation involves five climatic regions in the national. Then analysis the energy-saving of the two types of heat exchanger in different area. The result shows that, energy saving effect by using the technology was significant; in city of Kunming(warm region) the annual power saving rate is the highest, about 39% (plate heat exchanger); in city of Guangzhou(region of hot summer and warm winter) the annual power saving rate is the lowest about 14% (plate heat exchanger); the energy saving effect of plate heat exchanger is close to the effect of gravity heat pipe heat exchanger.
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