Modeling of energy characteristics of atmospheric boundary layer

Abstract

The paper contains some experimental data obtained in modeling the atmospheric boundary layer in the Landscape Wind Tunnel, a new test facility of the Krylov State Research Centre. The test facility, measurement techniques and test data processing methods are described. The atmospheric boundary layer is modelled in the long test section of this wind tunnel using vortex generators in the form of cones and prism-shaped discrete roughness elements. All flow characteristics are measured using thermoanemometry techniques. A case study of modeling the average and pulsation velocity profile is used to demonstrate that the atmospheric boundary layer can be modelled not only in terms of average characteristics but also in terms of the main energy characteristics with acceptable accuracy for engineering applications. Modelled average characteristics have been verified by comparing the experimental data with the data contained in regulatory documentation on determination of natural wind loads. Correct reproduction of energy characteristics is ensured based on agreement with the known energy relationships: “−5/3” law, approximations of Davenport, Karman, Liepmann. It is concluded that, in principle, special-purpose wind tunnels with long test sections are able to simulate the main characteristics of atmospheric boundary layer for various types of terrain.