A laboratory model of severe downslope winds

James W. Rottman; Ronald B. Smith

doi:10.3402/tellusa.v41i5.11849

A laboratory model of severe downslope winds

Tellus

Volume 41 (1989): Issue 5

By: James W. Rottman and Ronald B. Smith

Open Access

|Jan 1989

Abstract

Laboratory experiments are described in which flow visualization techniques were used to investigate the conditions under which a severe downslope wind may exist for linearly stratified flow over a ridge when the upstream flow is shear free. Three different ridges with similar cross sections but with maximum slopes of 40°, 27° and 13° were used. In the experiments for each ridge, the Froude number F = U/(NH), where U is the free stream speed, N is the buoyancy frequency and H is the ridge height, was varied over the full range in which internal wave breaking was anticipated. The range of F over which a well-mixed region of turbulent fluid formed above the ridge was determined for each of the three ridges. This well-mixed region was observed to occur generally in conjunction with a strong downslope flow on the lee side of the ridge. The results of the laboratory experiments are compared with previous numerical simulations and with a nonlinear hydrostatic theory for severe downslope winds.

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Articles in this issue

DOI: https://doi.org/10.3402/tellusa.v41i5.11849 | Journal eISSN: 3035-9554

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Language: English

Page range: 401 - 415

Submitted on: Apr 6, 1988

Accepted on: Jan 23, 1988

Published on: Jan 1, 1989

Published by: Stockholm University Press

In partnership with: Paradigm Publishing Services

© 1989 James W. Rottman, Ronald B. Smith, published by Stockholm University Press
This work is licensed under the Creative Commons Attribution 4.0 License.

Volume 41 (1989): Issue 5