Entropic analysis of adsorption open cycles for air conditioning. Part 2: interpretation of experimental data

✍ Scribed by Akio Kodama; Weili Jin; Motonobu Goto; Tsutomu Hirose; Michel Pons

• Publisher: John Wiley and Sons
• Year: 2000
• Tongue: English
• Weight: 216 KB
• Volume: 24
• Category: Article
• ISSN: 0363-907X
• DOI: 10.1002/(sici)1099-114x(20000310)24:3<263::aid-er579>3.0.co;2-m

✦ Synopsis

24: 251}262) is applied to experimental results. That approach takes into account the irreversibilities due to the open character of the cycle. Measurements are performed on a solid desiccant cooling unit operated in the ventilation mode. Experimental data permit us to establish the entropy balance of the unit. The results show that the sum of all the considered entropy productions completely explain the di!erence between the Carnot COP and the actual COP of the unit. The e!ects of three experimental parameters are investigated: the rotation speed of the dehumidi"er (desiccant wheel), the air velocity and the regeneration temperature. Experimental results show that there exists an optimal rotation speed which results from a combination between the di!erent entropy productions in the cycle. When the air velocity is increased, together with an accordingly optimized rotation speed, the cooling capacity increases while the COP decreases due to increases in the entropy productions in the dehumidi"er and sensible heat exchanger. Moreover, it appears that the most signi"cant entropy productions take place in the dehumidi"er and heating system. In the investigated experimental unit, these two entropy productions have similar magnitudes. However, when the regeneration temperature is increased, the irreversibilities due to mass exchanges with outside air become comparable to these and surely should not be forgotten in a global optimization of the process. The present analysis is a solid basis for reducing the largest entropy productions thus optimizing the process.