Investigation of the use of silicone sponge tube and design study of other components in solar thermal collector

北欧的大多数太阳能热系统都有一个单独的防冻液填充回路，以防止冻结，并且需要一个装有热交换器的新水箱。在改造现有房屋时，这意味着需要更换一个完美的水箱（通常是铜的）。我们开发了一种创新的解决方案，可以直接加热生活用水，而不需要二次流体循环。这提高了系统的效率，降低了资金和安装成本。我们的解决方案允许系统冻结，但不会造成系统损坏，通过在外部铜管内使用可压缩闭孔硅胶海绵管。当它冻结时，可压缩管吸收由于冰而产生的膨胀，防止压力积聚和对系统的损坏。本研究将通过在实际情况和冷冻试验中试验各种规格和尺寸的硅胶海绵管来确定最佳规格。

Most solar thermal systems in Northern Europe have a separate antifreeze filled loop for protection against freezing and require a new tank fitted with a heat exchanger. When retrofitting to existing homes this means that a perfectly good tank (usually copper) needs to be replaced. We have developed an innovative solution that allows a domestic water supply to be heated directly, without the secondary fluid cycle. This increases the efficiency of the system and reduces capital and installation costs. Our solution allows the system to freeze but cause no system damage by using a compressible closed cell silicone sponge tube within an outer copper pipe. When it freezes the compressible tube takes up the expansion due to the ice and prevents pressure build up and damage to the system. This study will determine the optimum specification of the silicone sponge tube by trialling various specifications of tubes and sizes in a real world situation as well as freeze tests.