Conformal adaptive hexahedral-dominant mesh generation for CFD simulation in architectural design applications

Mesh generation is a critical and probably the most manually intensive step in CFD simulations in the architectural domain. One essential feature is the large span of dimensional scales that is encountered in design, particularly if the model aims to simulate indoor and outdoor conditions concurrently, e.g., site at the magnitude of kilometers while building elements at the magnitude of centimeters. In addressing the challenge this paper presents an approach to generate adaptive hexahedral-dominate meshes for CFD simulations in sustainable architectural design applications. Uniform all-hexahedral meshes and adaptive hexahedral-dominant meshes are both generated for natural ventilation simulation of a proposed retrofit building in Philadelphia. Simulation results show that adaptive hexahedral-dominate meshes generate very similar results of air change rate in the space due to natural ventilation, compared to all-hexahedral meshes yet with up to 90% reduction in number of elements in the domain, hence improve computation efficiency.