Coupling Phase Change Materials and Model Predictive Controls for Energy Efficiency and Thermal Comfort in Canadian Buildings

围护结构的热性能要求变得越来越严格，最常见的合规方法是添加更多的绝缘材料。在许多情况下，由于空间限制和更多地使用玻璃幕墙系统，这可能不切实际。另一种方法是通过加入相变材料来增加建筑围护结构的储热能力。相变材料是一种创新产品，能够通过从液体到固体的相变来储存和释放单位质量的大量热量，并在接近典型室温的情况下进行存储和释放。其想法是，PCM在白天融化时吸收建筑物的部分热负荷，并在较凉爽的夜间通过返回固相释放热量。在夏天，释放的热量将通过自然通风或风扇排出，而在冬天，它将减少供暖需求。然而，在建筑物中成功且经济高效地应用相变材料取决于对许多因素的仔细选择，包括：工作温度范围、材料厚度、空间内的位置以及建筑构件内的位置。此外，相变材料应该能够在夜间完全释放其吸收的能量才能充分发挥作用。这通常需要改变供暖、通风和空调(HVAC)系统的运行方式。模型预测控制(MPC)是一种多变量控制算法，可以用来取代传统的暖通空调控制策略，并为相变材料在24小时内实现完全相变提供最佳条件。预测控制考虑建筑系统的热响应和未来预测的气候条件，以预测系统的行为，并提前应用适当的控制输入。因此，将相变材料和基于MPC的系统相结合，可以在建筑中实现节能和改善热舒适性。研究人员、建筑业、能源政策制定者和业主对PCM和基于MPC的建筑系统有广泛的兴趣。预计到2019年，全球PCM市场将从2013年的4.6亿美元增长到15亿美元。然而，PCM增强材料的热物理性质及其有效的建筑集成还没有完全被了解。需要进一步研究开发更稳健和可靠的算法，以应对阻碍基于MPC的技术的商业可行性的挑战。拟议研究计划的目标是为将PCM和基于MPC的系统集成到建筑物中开发最佳设计战略和解决方案，以促进和支持国家建筑规范的变化和这些技术的更广泛使用。在这个为期5年的周期中，五名学生将通过一系列创新的实验室实验、实地研究和建模练习来培训，成为加拿大未来在潜热和先进的暖通空调控制技术方面的专家。

Envelope thermal performance requirements are becoming more stringent and the most common compliance approach is to add more insulation. In many cases this may not be practical due to space constraints and greater use of glazing façade systems. An alternative approach is to increase building envelope's thermal storage capacity by incorporating Phase Change Materials. PCMs are innovative products able to store and release large quantities of heat per unit of mass through a phase change from liquid to solid and back near typical room temperatures. The idea is that PCM absorbs part of a building's heat load during the daytime as it melts and releases this heat during the cooler night-time by returning to its solid phase. In the summer, the released heat would be flushed out using natural ventilation or fans, while in the winter it would reduce the heating requirements. However, successful and cost effective application of PCMs in buildings depends on careful selection of many factors including: working temperature range, material thickness, location within the space, and location within the building component. Additionally, the PCM material should be able to completely discharge its absorbed energy during the night to be fully effective. This often requires changes in the operation of heating, ventilation and air-conditioning (HVAC) systems. Model predictive control (MPC) is a multivariable control algorithm that can be used to override conventional HVAC control strategies and provide optimal conditions for a complete phase transition of PCMs in 24-hr. MPC considers thermal response of building systems and future projected climatic conditions to predict the behavior of the systems and apply the appropriate control inputs in advance. Therefore, coupling PCM and MPC-based systems could result in energy savings and thermal comfort improvement in buildings. There is wide interest in PCM and MPC-based building systems by researchers, the construction industry, energy policy makers and home owners. The global PCM market is estimated to grow from $460 million in 2013 to $1.5 billion by 2019. However, the thermo-physical properties of PCM-enhanced materials and their effective building integration have not been fully understood. Further research on development of more robust and reliable algorithms is needed to address challenges that inhibit commercial feasibility of MPC-based technologies. The objective of the proposed research program is to develop optimal design strategies and solutions for integrating PCM and MPC-based systems into buildings that will promote and support changes in the national building codes and the wider use of these technologies. In this 5-year cycle, five students will be trained through a series of innovative laboratory experiments, field studies, and modeling exercises to become Canada's future experts in latent heat and advanced HVAC control technologies.