二级吸收式热变换器比较研究

【作者】 向平；

【导师】 徐士鸣；

【作者基本信息】 大连理工大学 ， 制冷及低温工程， 2002， 硕士

【摘要】 目前在工业生产、尤其是石化行业生产中，存在大量的低温余热，而其中的大部分还可以被回收利用。实际中通常的做法是将这些废热直接排向自然环境。这不仅将污染我们所赖以生存的环境，对其造成热污染，而且还是能源的极大浪费，尤其是对我们这样一个能源紧缺的国家来说。 针对如上所述的实际用能情况，本文对三种循环方式的二级吸收式热变换器进行了研究，以分析用其回收这些余热的可行性。文中建立了这三种循环方式的二级吸收式热变换器的数学模型，并将一种新的制冷工质TFE／TEGDME用于这些系统。文章中分析了热源温度、热源在系统中的温降、对外供热温度、冷却水温度、循环放气范围等的变化对系统热回收量和回收品质的影响。 计算结果显示，在所计算的三种方式的循环中、在所研究的参数变化范围内，高低型循环的COP大体维持在0.32～0.34的范围内、COE大体维持在0.53～0.6的范围内，并联型循环的COP大体维持在0.29～0.32的范围内、COE大体维持在0.48～0.53的范围内，而低高型循环的COP与温升是一对很尖锐的矛盾：温升在60℃左右时，COP只有0.1左右，而要达到较高的COP时，温升只能达到很低的30～40℃。 由此可以得出结论，在回收废热方面，从热力学角度来看，高低型二级热变换器具有很好的应用价值，并联型相对一般，而低高型根本不具有实际应用价值。更多还原

【Abstract】 There is a great amount of waste heat in industry, especially in petrol industry, most of which could be used again. In practice, it is output into the environment directly. This not only does harm to the environment by heat pollution, but also waste the heat. So to recover the heat is very important, especially for China, a country lack of energy.According to the fact as described above, three cycles of two-staged AHT are studied. The mathematic models of them are founded and computed with the new working pairs TFE/TEGDME. The effects of heat source temperature, temperature drop of heat source in systems, output temperature, temperature of cooling water, concentration range of cycle on the quantity and quality of recovered heat are analyzed in the paper.The results show that in the three cycles, in the concerned range of parameters, COP of the high-low cycle ranges between 0.32 and 0.34, COE ranges between 0. 53 and 0. 6. And COP of the parallel cycle ranges between 0. 29 and 0. 32, COE ranges between 0. 48 and 0. 53. As to the low-high cycle, its COP and temperature lift conflict with each other sharply. When temperature lift reaches 60癈, its COP is as low as 0. 1. And when COP reaches 0.3, temperature life is as low as 30 or 40.From the view of thermodynamics, conclusions can be drawn that the high-low cycle is good to be used to recover waste heat, the parallel cycle is not relatively, and the low-high cycle is not at all.更多还原