Exergetic Studies on Domestic and Industrial Solar Water Heaters (original) (raw)
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IOP Conference Series: Materials Science and Engineering, 2019
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Journal of Cleaner Production , 2012
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Solar Energy, 2015
In this paper, the exergy efficiency of a solar photovoltaic thermal (PVT) water collector is investigated experimentally and numerically. An experimental setup of PVT water collector is constructed and its operating parameters are measured. The measured parameters include solar radiation intensity, wind speed, ambient temperature, solar cells temperature, fluid inlet and outlet temperature, open circuit voltage, short circuit current, maximum power point voltage and maximum power point current, respectively. The numerical simulation of PVT water collector is carried out with the use of one-dimensional steady thermal model and four-parameter currentvoltage model. The various exergy components in PVT system is introduced and a modified equation for exergy efficiency in terms of exergy losses is obtained. Numerical simulation results are in good agreement with the experimental measurements, which are carried out. Finally, parametric studies have been carried out. The comparison between the modified exergy efficiency of the present work and the one given by previous literature shows that the modified exergy efficiency obtained in this paper has not the deficiencies of the exergy efficiency given by the previous literature and it shows exergy loss terms in PVT system directly.
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Chemical Industry and Chemical Engineering Quarterly, 2014
In engineering practice exergy can be used for technical and economic optimization of energy conversion processes. The problem of increasing energy consumption suggests that heating plants, i.e. hot water boilers, as energy suppliers for household heating should be subjected to exergy and energy analysis. Heating plants are typically designed to meet energy demands, without the distinguished difference between quality and quantity of the produced heat. In this paper, the energy and exergy analysis of a gas fired hot water boiler is conducted. Energy analysis gives only quantitative results, while exergy analysis provides an insight into the actually available useful energy with respect to the system environment. In this paper, a hot water boiler was decomposed into control volumes with respect to its functional components. Energy and exergy of the created physical model of the hot water boiler is performed and destruction of exergy and energy loss in each of the components is calcul...