TY - CPAPER AU - Xuan Luo AU - Yu-Hang Tang AU - Tianzhen Hong AB -

For building energy simulation at an urban-scale, solar shading calculations can be significantly slow when a large number of shading surfaces are considered in the solar shading calculations, due to the computational complexity of the geometry calculations. We developed a new algorithm using the ray-tracing technique to pre-calculate the sunlit fractions of all exterior surfaces in an urban district altogether. The ray tracing-based calculator is accelerated using General Purpose Graphics Processing Units (GPGPUs) and the Optix ray tracing library, and provides an efficient, flexible, and robust means for computing the sunlit fraction of large numbers of urban surfaces of complex geometries. 

BT - 2020 Building Performance Analysis Conference and SimBuild co-organized by ASHRAE and IBPSA-USA DA - 08/2020 DO - DOI: 10.20357/B77606 LA - eng N2 -

For building energy simulation at an urban-scale, solar shading calculations can be significantly slow when a large number of shading surfaces are considered in the solar shading calculations, due to the computational complexity of the geometry calculations. We developed a new algorithm using the ray-tracing technique to pre-calculate the sunlit fractions of all exterior surfaces in an urban district altogether. The ray tracing-based calculator is accelerated using General Purpose Graphics Processing Units (GPGPUs) and the Optix ray tracing library, and provides an efficient, flexible, and robust means for computing the sunlit fraction of large numbers of urban surfaces of complex geometries. 

PY - 2020 T2 - 2020 Building Performance Analysis Conference and SimBuild co-organized by ASHRAE and IBPSA-USA T3 - 2020 Building Performance Analysis Conference and SimBuild co-organized by ASHRAE and IBPSA-USA TI - Efficient Computation Of Surface Sunlit Fractions In Urban-Scale Building Modeling Using Ray-Tracing Techniques ER -