E. A. Malinovskaya, G. I. Gorchakov, A. V. Karpov, L. O. Maksimenkov, O. I. Datsenko
{"title":"On the Conditions of the Emergence of a Periodic Mode of Saltating Flow","authors":"E. A. Malinovskaya, G. I. Gorchakov, A. V. Karpov, L. O. Maksimenkov, O. I. Datsenko","doi":"10.1134/s0001433823330022","DOIUrl":null,"url":null,"abstract":"<h3 data-test=\"abstract-sub-heading\">Abstract</h3><p>The effect of the emergence of quasi-periodic oscillations of particle (with size >50 mсm) concentrations in the saltation flow has been detected in similar arid conditions in desertified areas: (1) using high-speed video in Astrakhan region (2009); (2) by acoustic method in the Republic of Kalmykia (2021). During the field experiments were revealed characteristic low frequencies (<50 Hz), which is associated with the peculiarities of the microrelief shape. More high frequences (>50 Hz) have been observed also. The appearance of these frequencies is determined by changes in the saltation cycle in heterogeneous topography. Such processes is simulated in a numerical experiment using the OpenFoam package. There are demonstrated the characteristic frequencies of changes in the number of particles (from 10 to 200 Hz) in the saltation flow over the surface ledge of the ripple type. Numerical experiments include analysis of frequency characteristics of particle concentration changes in the flow behind the ledge. Spectral analysis of data of numerical realizations of the saltation flow at variation of boundary parameters and height of the obstacle shows that the characteristic frequency or frequencies change and are close to those observed in the experiment. Input parameters such a models can be adjusted with such analysis.</p>","PeriodicalId":54911,"journal":{"name":"Izvestiya Atmospheric and Oceanic Physics","volume":"29 1","pages":""},"PeriodicalIF":0.9000,"publicationDate":"2023-12-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Izvestiya Atmospheric and Oceanic Physics","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.1134/s0001433823330022","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"METEOROLOGY & ATMOSPHERIC SCIENCES","Score":null,"Total":0}
引用次数: 0
Abstract
The effect of the emergence of quasi-periodic oscillations of particle (with size >50 mсm) concentrations in the saltation flow has been detected in similar arid conditions in desertified areas: (1) using high-speed video in Astrakhan region (2009); (2) by acoustic method in the Republic of Kalmykia (2021). During the field experiments were revealed characteristic low frequencies (<50 Hz), which is associated with the peculiarities of the microrelief shape. More high frequences (>50 Hz) have been observed also. The appearance of these frequencies is determined by changes in the saltation cycle in heterogeneous topography. Such processes is simulated in a numerical experiment using the OpenFoam package. There are demonstrated the characteristic frequencies of changes in the number of particles (from 10 to 200 Hz) in the saltation flow over the surface ledge of the ripple type. Numerical experiments include analysis of frequency characteristics of particle concentration changes in the flow behind the ledge. Spectral analysis of data of numerical realizations of the saltation flow at variation of boundary parameters and height of the obstacle shows that the characteristic frequency or frequencies change and are close to those observed in the experiment. Input parameters such a models can be adjusted with such analysis.
期刊介绍:
Izvestiya, Atmospheric and Oceanic Physics is a journal that publishes original scientific research and review articles on vital issues in the physics of the Earth’s atmosphere and hydrosphere and climate theory. The journal presents results of recent studies of physical processes in the atmosphere and ocean that control climate, weather, and their changes. These studies have possible practical applications. The journal also gives room to the discussion of results obtained in theoretical and experimental studies in various fields of oceanic and atmospheric physics, such as the dynamics of gas and water media, interaction of the atmosphere with the ocean and land surfaces, turbulence theory, heat balance and radiation processes, remote sensing and optics of both media, natural and man-induced climate changes, and the state of the atmosphere and ocean. The journal publishes papers on research techniques used in both media, current scientific information on domestic and foreign events in the physics of the atmosphere and ocean.