Making the Urban Sky View Factor With Numerical Models Consistent With Radiation Heat Transfer Theory

Abstract

This work proposes a method for removing the inconsistency between the numerical models used for determining the sky view factor (SVF) in an urban environment and fundamental radiation heat transfer theory. For this purpose, a transformation of the coordinate system from global to surface was developed, which corrected the measurement of the angular coordinates of the elements in the discretized sky vault. The transformation was deployed in a published numerical model and was validated in a non-urban environment with a widely used analytical expression for the SVF, with which it was found to be in excellent agreement. The method was subsequently applied to an urban scenario, and the results were compared with the original numerical model. The proposed method provides a better determination of the SVF as a function of the surface azimuth and tilt angle.