Using Taguchi-Fibonacci search method to optimize phase change materials enhanced buildings with integrated solar photovoltaic thermal collectors
This paper presents optimization of phase change materials (PCMs) enhanced buildings with integrated air-based solar photovoltaic thermal (PVT) collectors, where PCMs are embedded into building envelopes to increase local thermal mass, while the heated air from PVT collectors is directly used for space heating. The objective of the optimization is to maximize the Signal-to-Noise (S/N) ratio of Coefficient of Thermal Performance Enhancement (CTPE) of buildings. The factors optimized are the PVT air flow rate, PCM type, PCM layer thickness and additional wall insulation. Taguchi-Fibonacci search method integrating Taguchi method and Fibonacci search method is developed to solve this optimization problem with continuous and discrete variables. Analysis of Variance is used to determine the percentage contribution of each optimization factor. The simulation results based on a typical Australian house showed that the optimal PVT air flow rate, additional wall insulation, optimal PCM type among the PCMs studied and PCM layer thickness in the search ranges defined were 1640.4 kg/h, 3.0 m2·K/W, SP21E PCM and 30 mm, respectively. Compared to the results without optimization, the CTPEs of the house improved from 45.54 to 72.22%. Taguchi-Fibonacci search method can be useful for solving multi-dimensional design optimization problems with both discrete and continuous variables.