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.

中文翻译：

---

具有新型可变容积水箱的太阳能热水系统的长期性能

摘要 最近设计了一种新型的可变容积罐，以适应罐容积的不同需求。基于集热器和新型储罐的验证模型，本文提出了具有新型储罐的太阳能供暖系统的数学模型。该系统专为空间供暖而设计，由太阳能集热器、可变容量水箱和辅助热源组成。以使用太阳能供暖系统进行空间供暖的办公楼为例进行了研究。模拟和研究了系统在 4 个月的供暖季节的热行为。研究案例表明，与传统系统相比，新型储罐系统在提供 11.6% 的有用热量和减少 19% 的系统热损失方面具有明显优势。还进行了参数研究以分析储罐绝缘的影响，罐容积和收集器尺寸对系统长期性能的影响。结果表明，新型储罐系统的长期性能对储罐绝缘性能下降或储罐体积过大具有更强的弹性，这有助于建立强大的加热系统以应对极端操作条件。