Evaluation of the performance for a dynamic insulation system suitable for switchable building envelope

This paper evaluates a prototype of dynamic insulation systems (DIS) suitable for switchable building envelope to minimize heating and cooling thermal loads while maintaining indoor thermal comfort. The thermal performance of the novel DIS prototype has been evaluated through both experimental and numerical analyses when applied to an opaque wall section. The DIS prototype is able to vary continuously the R-value of the building envelope using rotating insulation layers controlled through an actuator to a specific angle depending on the desired thermal resistance level. The experimental testing showed that the prototype DIS provides a significant reduction of over 50% of the wall R-value when the insulation layers no longer overlap due to the increased convection inside the wall cavity. The CFD analysis predictions, matching the experimental results, demonstrate that the DIS prototype offers a simple design option that can be easily controlled and modulated to adjust the R-value of the building envelop based on the angle of the insulation layers. The CFD analysis also showed that the DIS performance depends on several design features including the depth of the wall cavity as well as the width and the thickness of the insulation layers. (C) 2020 Elsevier B.V. All rights reserved.