SIMULATION FOR REVERSE FLOW ANALISYS IN FLAT-PLATE COLLECTORS WITH THERMOSIPHON SYSTEMS
DOI:
https://doi.org/10.59627/cbens.2008.1380Keywords:
Solar Energy, Reverse Flow Circulation, Computational SimulationAbstract
In the solar water heating systems (SWHS), an important factor in its application is the analyses of its performance. Experimental tests are made and compared with the results obtained from the software simulations that are developed, in order to improve the capacity of analysis, with reliable results and saving time. Heat losses are present in the SWHS, during the day and night, but the heat losses during the night in general are neglected. A few published articles revealed that an appropriate installation minimizes the thermal losses. With the objective to study this phenomena, called reverse circulation, it was incorporated in the software Termosim, developed by Solar Energy Lab from UFRGS, the heat losses calculus making possible the analysis of this issue changing geometric parameters of the system. This paper describes the mathematical models applied in the calculations of reverse flow circulation and energy losses associate to it. The simulations made resulted that the heat losses at night are minimized as much as the distance between the bottom of the tank and the top of the collector is bigger, and it can have a significant impact in the temperatures in a stratified tank.
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References
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