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Neutrally stable atmospheric flow over a two-dimensional rectangular block

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Bibliographic Details
Title: Neutrally stable atmospheric flow over a two-dimensional rectangular block
Authors: Shieh, C. F., Bitte, J., Frost, W.
Source: CASI
Publication Year: 1977
Collection: NASA Technical Reports Server (NTRS)
Subject Terms: METEOROLOGY AND CLIMATOLOGY
Subject Geographic: Unclassified, Unlimited, Publicly available
Description: The phenomena of atmospheric flow over a two dimensional surface obstruction such as a building modeled as a rectangular block are analyzed by an approach using the Navier-Stokes equations with a two equation model of turbulence. The partial differential equations for the vorticity, stream function, turbulence kinetic energy, and turbulence length scale are solved by a finite difference technique. The predicted results are in agreement with the limited experimental data available. Current computed results show that the separation bubble originates from the upper front corner of the block and extends approximately 11.5 block heights behind the block. The decay of the mean velocity along the wake center line coincides almost perfectly with the experimental data. The vertical profiles of the mean velocity defect are also in reasonable agreement with wind tunnel results. Velocity profiles in the mixing region are shown to agree with the error function profile typically found in the shear layer. Details of the behavior of the turbulence kinetic energy and the turbulence length scale are also discussed.
Document Type: other/unknown material
File Description: application/pdf
Language: unknown
Relation: Document ID: 19780004685; Accession ID: 78N12628; http://hdl.handle.net/2060/19780004685
Availability: http://hdl.handle.net/2060/19780004685
Rights: No Copyright
Accession Number: edsbas.4C75FF30
Database: BASE
Description
Abstract:The phenomena of atmospheric flow over a two dimensional surface obstruction such as a building modeled as a rectangular block are analyzed by an approach using the Navier-Stokes equations with a two equation model of turbulence. The partial differential equations for the vorticity, stream function, turbulence kinetic energy, and turbulence length scale are solved by a finite difference technique. The predicted results are in agreement with the limited experimental data available. Current computed results show that the separation bubble originates from the upper front corner of the block and extends approximately 11.5 block heights behind the block. The decay of the mean velocity along the wake center line coincides almost perfectly with the experimental data. The vertical profiles of the mean velocity defect are also in reasonable agreement with wind tunnel results. Velocity profiles in the mixing region are shown to agree with the error function profile typically found in the shear layer. Details of the behavior of the turbulence kinetic energy and the turbulence length scale are also discussed.