A method of simulating the surface roughness of complex terrain based on openfoam

Abstract

The invention belongs to the field of computing wind engineering, and discloses an OpenFOAM-based method for simulating complex terrain surface roughness. The method comprises the following steps of 1) building a complex terrain CFD model, and generating a refined grid; 2) extracting surface roughness length data of the complex terrain CFD model, converting a surface roughness length into a surface cover vegetation height, and providing an accurate data basis for simulating an influence of a surface cover vegetation on a wind field of a complex terrain; 3) calculating resistance coefficients of the surface cover vegetation to the wind field at different heights, and then converting the surface cover vegetation height into the corresponding resistance coefficient; and 4) adding the resistance coefficient and a resistance item of the surface cover vegetation by using OpenFOAM, thereby obtaining a more accurate complex terrain wind field characteristic simulation result. A program language supported by a computer is used; the influence of the surface roughness on the wind field of the complex terrain is considered; and therefore, the numerical simulation accuracy of the wind field ofthe complex terrain is improved.

Description

Technical field

[0001] The invention belongs to the field of computational wind engineering, and more specifically, relates to a method for simulating the surface roughness of complex terrain. Background technique

[0002] The surface roughness length means that due to the influence of the unevenness of the surface or the geometry of the ground features, the position where the wind speed is zero on the wind speed profile is not on the surface (where the height is zero), but at a certain height from the surface. This height is also called the aerodynamic roughness length, which is a comprehensive characteristic parameter that affects the shape and retarding force of the passing fluid. The length of the surface roughness is caused by vegetation on the surface, which represents the aerodynamic characteristics of the surface, reflects the weakening effect of the surface on the wind speed, and depends on the roughness factors, such as the geometry, size and height, distribution type a...

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