Study of Dynamics of Heat Transfer in the Flat-Plate Solar Collector

Processes

Andrzej Chochowski¹  Joanna Aleksiejuk-Gawron¹ 

[1] Department of Fundamentals in Engineering and Energy, Institute of Mechanical Engineering, Warsaw University of Life Sciences, 02-787 Warsaw, Poland;

关键词: heat transfer;    heat exchanger;    solar collector;    step response;    thermoelectric analogy;   

DOI  :  10.3390/pr8121607

来源: DOAJ

【 摘 要 】

Flat plate solar collector has been presented as an example of a heat-exchanger with two input signals, solar radiation intensity and temperature of working medium on the input, and one output signal, the temperature of a working medium on the output. The dynamics of heat exchange were analyzed for two models of a solar collector—an analog one using a thermoelectric analogy, and a digital one—determined experimentally in on-line mode using the parametric identification method. The characteristics of both models were compared in terms of their step and frequency response for selected construction and operational parameters. Tests of step responses determined for the analog model indicate that the dynamics of heat exchange in the solar collector depending on two input signals is varied. For step-forcing of input signals of the analog model, in both cases, a stable steady state is achieved, but while the first of the signals is inertial, the second one is oscillatory. The phenomenon of temperature oscillation at the collector outlet suggests the need to introduce a new physical quantity in the thermoelectric analogy-thermal inductance. Such an assessment of the dynamics of the solar collector can be useful for proper designing (construction parameters simulation) and diagnostics (operational parameters simulation) of the device.

【 授权许可】

Unknown