Implementation of a detailed shadow model into the EULAG CFD model for urban applications: Madrid case study

摘要

The urban energy exchange is a fundamental issue for urban scale meteorological simulations. It is necessary to calculate the transfer of energy and momentum between the urban surface and the atmosphere with more realistic urban geometry. Urban energy fluxes can be obtained applying the surface energy balance equation. A new three-dimensional urban solar radiation model (SHAMO) has been developed to calculate short wave radiation over urban high resolution grids. The model needs the following inputs: sun location and global short radiation which are taken from the mesoscale runs developed with the meteorological model WRF (NCAR, US) and building structures from geographic information databases. The data produced by the urban solar radiation model has been used in large scale numerical experiments to simulate turbulent fluxes for urban areas, over Madrid (Spain) city. We have applied a modified version of the EULAG (UCAR) micro scale model (CFD) which includes an energy balance equation to obtain the urban energy exchange. Results of the micro scale simulations and how sensitivity are the results to the solar radiation approach will be presented in this chapter.