Analytical solution for energy modeling of double skin façades building

Double skin façade (DSF) building is one of the available energy conservation opportunities through recent intelligent buildings. In this research, an innovative point of view to analyze a DSF with energy consideration is appointed, at a glance. To propose this subject, absorbed solar energy plus contributed critical scenarios have been formulated. Continually, the wind energy and temperature and relative humidity effects, and dew formation for condensate appearance on the surface have been technically investigated to complete the simulation. Introducing differential equations is the main part of this study which indicates heat transfer characteristics through the trapped air at skins spacing. In order to cover that, empirical equations plus energy, continuity and momentum differential equations, related to natural convection on vertical thermal shield have been developed. The analytical solution method, with extracted velocity vector and temperature profile, is the other advantage of this research. For a desired building, velocity and temperature variations are defined bounded to façades geometry and spacing. The temperature and velocity profiles have been illustrated by MATLAB software, by increasing grid nodes. Finally, results on techno-economical modeling by which acceptable range of indexes could be explained have been tabulated.

► An innovative point of view to analyze a double façades building with energy consideration. ► Techno-economical approach and feasibility study on double skin façades building. ► Simple payback estimated 3 years and 5 months. ► Total net profit value (NPV) would be equal to 657,883.94 ($). ► Its internal rate of return (IRR) is approximately 29.87%.