Modeling, Simulation, and Performance Analysis of a Liquid-Infill Tunable Window

Solar shading is important in buildings for better indoor thermal/light environment and energy conservation, especially in the tropical region. Compared with conventional windows with additional fixed shading devices, windows with adaptive self-shading functions take up less space and require less management labor. The present investigation focuses on a compact liquid-infill tunable window, which can provide adaptive shading with colored liquid-infill according to the surrounding environment. The numerical model of the liquid-infill tunable window was established on the basis of the law of energy and mass conservation, which enabled prediction of the adaptive response of the window under different boundary conditions. Then the thermal performance of this innovative window was analyzed in comparison with triple-layered clear glass windows. Influences of solar radiation level, incident angle, and ambient temperature were taken into consideration. The window was proven to be efficient in reducing indoor heat gain in the cooling season under strong solar radiation. With an 60° incident angle, the total indoor heat gain through window can be reduced by 1.60–8.33%. In the future, the established numerical model may be inserted into existing building simulation software as an energy-efficient window module to evaluate its energy and economic performance. The present study may inspire architectures and engineers in the design of near-zero energy and/or carbon neutral buildings.