Optimizing Device Performance of Multi-pass Flat-plate Solar Air Heaters on Various Recycling Configurations
學年 111
學期 2
出版(發表)日期 2023-03-08
作品名稱 Optimizing Device Performance of Multi-pass Flat-plate Solar Air Heaters on Various Recycling Configurations
著者 Chii-Dong Ho; Hsuan Chang; Chih-Wei Yeh; Choon Aun Ng; Ping-Cheng Hsieh
著錄名稱、卷期、頁數 Energies 16(6), p.2568-2590
摘要 Various external-recycle configurations of multi-pass flat-plate solar air collectors were studied theoretically to examine the optimal thermal performance under the same working dimension and operation conditions. An absorber plate and insulation sheet were implemented horizontally and vertically, respectively, into an open rectangular conduit to conduct a recycling four-pass operation, which the device lengthens the air flow channel and increases the air mass flow rate within the collector, and thus, a more heat transfer efficiency is obtained. Four recycling types with different external-recycle patterns were introduced and expected to augment the heat transfer rate due to the turbulent convective intensity through four subchannels in the present study. Coupling energy balances into one-dimensional modeling equations were derived by making the energy-flow diagram within a finite element, which the longitudinal temperature distributions for each subchannel were obtained. The theoretical predictions show that the improved four-pass device is accomplished due to the multiple heating pathways over and under the absorber plate, from which the turbulence intensity augmentation results in the heat transfer rate as compared to that in the device without inserting the absorber plate and insulation sheet (say a downward-type single-pass solar air collector). The theoretical results also show that the external-recycle configuration (say Type C in the present study) acts as an optimal collector thermal efficiency and leading to a beneficial design in multi-pass solar air collectors for improving heat-transfer rate and increasing resident time under the same operation conditions. Theoretical predictions show a higher heat-transfer efficiency for the present recycling configurations up to a maximum 115% device enhancement in comparison to that of a single-pass device. Examination of implementing the absorber plate and insulation sheet on the heat-transfer efficiency enhancement as well as the hydraulic dissipated power increment were also delineated, and deliberated the suitable external-recycle configuration with respect to an economic consideration.
關鍵字 thermal efficiency;four-pass operation;solar air collector;recycling operation;hydraulic dissipated power
語言 en_US
ISSN 1996-1073
期刊性質 國外
收錄於 SCI EI
國別 CHE
出版型式 ,電子版

機構典藏連結 ( http://tkuir.lib.tku.edu.tw:8080/dspace/handle/987654321/123275 )