Observations of Stably Stratified Flow through a Microscale Gap

نویسندگان

چکیده

Abstract This paper reports the findings of a comprehensive field investigation on flow through mountain gap subject to range stably stratified environmental conditions. study was embedded within Perdigão campaign, which conducted in region parallel double-ridge topography with ridge-normal wind climatology. One ridges has well-defined (col) at top, and an array situ remote sensors, including novel triple Doppler lidar system, deployed around it. The experimental design mostly guided by previous numerical theoretical studies idealized configuration where (with characteristic velocity U 0 buoyancy frequency N ) approaches normal height h its crest, for governing parameters are dimensionless G = Nh / various aspect ratios. Modified forms were proposed account real-world atmospheric variability, results discussed terms gap-averaged value c . nature highly dependent , wherein nearly neutral regime ( < 1), transitional wave [ ~ O (1)], gap-jetting > (1)] identified. measurements broad agreement single ridge or topography, although details vary. is first-ever detailed reported microscale (100) m] flows, it provides useful data insights future studies.

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ژورنال

عنوان ژورنال: Journal of the Atmospheric Sciences

سال: 2021

ISSN: ['1520-0469', '0022-4928']

DOI: https://doi.org/10.1175/jas-d-20-0087.1