Development of higher order urban computational modelling procedures, data comparison and calibration

有许多信息可以从实验方法中获得；然而，这些方法受到限制，包括无法在建筑施工之前进行全面的实验，或无法同时测量现有结构内的所有点。计算流体动力学(CFD)允许以计算能力为代价获得全尺度和全场流动信息。困难在于，到目前为止，大型流场模型一直依赖于基于雷诺平均方法(RANS)的模型。大涡模拟，或大涡模拟，已经成为计算密集型模拟的选择方法，并解决了必要的规模。传统的RAN虽然有用，但需要重要的假设，这些假设会损害所获得的流动物理的保真度。直接数值模拟(直接数值模拟)由于其计算要求，仍然是一种无法解决所有尺度问题的方法。LES是RAN和DNS之间的桥梁，其中充满活力的 大比例尺是直接分解和计算的，而较小的、更通用的比例尺是建模的。通过对惯性子范围内的子网格尺度进行建模，可以提取可用于改善局部条件的高保真流动信息。

There is much information to be obtained from experimental methods; however, these suffer from limitations including the inability to perform full-scale experiments in advance of building construction or to measure all points simultaneously within an existing structure. Computational Fluid Dynamics (CFD) allows full-scale and whole-field flow information at a cost of computational power. The difficulty is that to date, large flow field models have depended on Reynolds-averaged methods (RANS) based model. Large-Eddy Simulation, or LES, has become the method of choice for computationally-intensive simulations resolved to the necessary scales. Traditional RANS, although useful, require significant assumptions that compromise the fidelity of the flow physics obtained. Direct Numerical Simulation (DNS) which resolves all the scales remains a prohibitive method due to its computational requirements. LES bridges between RANS and DNS, where the energetic large scales are resolved and computed directly whereas the smaller more universal scales are modelled. By modeling the subgrid scales within the inertial subrange, it is possible to extract high-fidelity flow information that can be used to improve local conditions.