Modeling and simulation for the optimal switching temperature of double-glazed thermotropic window

A novel kind of smart thermotropic material was developed by a different mixing proportion of hydroxypropyl methyl cellulose (HPMC), Sodium Chloride (NaCl) and pure water. Switching temperature and switching speed from transparent state to light scattering state of thermotropic layer in a double-glazed window was analyzed with numerical simulation and the results show that thermotropic layer has the most significant changes in the heating rate in the first hour, especially in the first half hour. Its temperature reached 36.8°C and it can cause a reduction in light transmittance to below 25% with the optimal mixing proportion of HPMC, NaCl and pure water of 2∶10∶100 by mass, and the optimal switching temperature of double-glazed thermotropic window is 31.5°C.