[Clean Energy]

Jarong Li,Xiangdong Li,Yong Wang, Jiyuan Tu. Long-term performance of a solar water heating system with a novel variable-volume tank [J]. Renewable Energy, 2020, 164:230-241.

Keywords: Variable-volume tank；Long-term performance；Solar space heating；Mathematical model

High Lights:

A mathematical model for solar heating system with new tank design is proposed

The new tank improves the heat supply performance of the heating system

The new tank reduces the heat loss of the heating system.

The new tank helps build a more robust solar heating system

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Abstract:

A novel variable-volume tank is lately designed to cater for the varying needs of tank volume. Based on the validated models of collector and the novel tank, a mathematical model for the solar heating system with the novel tank is proposed in this paper. The system is designed for space heating and consists of solar collector, variable-volume water tank and auxiliary heat source. A case of office building using the solar heating system for space heating is studied. The thermal behaviour of the system during a 4-month heating season is simulated and investigated. The studied case shows that the novel tank system has clear advantage in providing 11.6% more useful heat and reducing 19% system heat loss compared to a conventional system. A parametric study is also conducted to analyse the impacts of tank insulation, tank volume and collector size on the long-term system performance. The results show that the long-term performance of the novel tank system is more resilient to a degraded tank insulation or an oversized tank volume, which contributes to a robust heating system to cope with extreme operating conditions..

Resource：https://www.sciencedirect.com/science/article/pii/S0960148120313884