{"title":"从波浪形跳跃过渡到突破跳跃","authors":"Manoj Langhi, Takashi Hosoda","doi":"10.1080/00221686.2023.2239188","DOIUrl":null,"url":null,"abstract":"ABSTRACTIn the present study, a one-dimensional governing equation with a vertical acceleration term is used to analyse the free surface profile of various types of jumps. Initially, the surface profile of various types of jumps are reproduced analytically by using a suitable eddy diffusivity term. The approximations of the surface profile for various jumps are then verified numerically. Based on the comparisons, an empirical relationship between the Froude number and the turbulent diffusivity coefficient is established. The proposed empirical relationship is used in the governing equation to compute the various jumps, where an implicit two dimensional flow is assumed. The obtained results are compared with the experimental data to assure the transition of flow from undular jump to breaking jump. The comparisons of numerical results of wave profiles, pressure distribution, wave length and wave amplitude with the existing experimental data for various Froude numbers indicated the suitability of the proposed empirical relationship. Finally, the transitions of flow from undular jump to breaking hydraulic jump are discussed.Keywords: Froude numberhydraulic jumpopen channel flowsurface profileundular jump","PeriodicalId":54802,"journal":{"name":"Journal of Hydraulic Research","volume":null,"pages":null},"PeriodicalIF":1.7000,"publicationDate":"2023-09-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":"{\"title\":\"Transition from undular jump to breaking jump\",\"authors\":\"Manoj Langhi, Takashi Hosoda\",\"doi\":\"10.1080/00221686.2023.2239188\",\"DOIUrl\":null,\"url\":null,\"abstract\":\"ABSTRACTIn the present study, a one-dimensional governing equation with a vertical acceleration term is used to analyse the free surface profile of various types of jumps. Initially, the surface profile of various types of jumps are reproduced analytically by using a suitable eddy diffusivity term. The approximations of the surface profile for various jumps are then verified numerically. Based on the comparisons, an empirical relationship between the Froude number and the turbulent diffusivity coefficient is established. The proposed empirical relationship is used in the governing equation to compute the various jumps, where an implicit two dimensional flow is assumed. The obtained results are compared with the experimental data to assure the transition of flow from undular jump to breaking jump. The comparisons of numerical results of wave profiles, pressure distribution, wave length and wave amplitude with the existing experimental data for various Froude numbers indicated the suitability of the proposed empirical relationship. Finally, the transitions of flow from undular jump to breaking hydraulic jump are discussed.Keywords: Froude numberhydraulic jumpopen channel flowsurface profileundular jump\",\"PeriodicalId\":54802,\"journal\":{\"name\":\"Journal of Hydraulic Research\",\"volume\":null,\"pages\":null},\"PeriodicalIF\":1.7000,\"publicationDate\":\"2023-09-25\",\"publicationTypes\":\"Journal Article\",\"fieldsOfStudy\":null,\"isOpenAccess\":false,\"openAccessPdf\":\"\",\"citationCount\":\"0\",\"resultStr\":null,\"platform\":\"Semanticscholar\",\"paperid\":null,\"PeriodicalName\":\"Journal of Hydraulic Research\",\"FirstCategoryId\":\"1085\",\"ListUrlMain\":\"https://doi.org/10.1080/00221686.2023.2239188\",\"RegionNum\":3,\"RegionCategory\":\"工程技术\",\"ArticlePicture\":[],\"TitleCN\":null,\"AbstractTextCN\":null,\"PMCID\":null,\"EPubDate\":\"\",\"PubModel\":\"\",\"JCR\":\"Q3\",\"JCRName\":\"ENGINEERING, CIVIL\",\"Score\":null,\"Total\":0}","platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Hydraulic Research","FirstCategoryId":"1085","ListUrlMain":"https://doi.org/10.1080/00221686.2023.2239188","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"ENGINEERING, CIVIL","Score":null,"Total":0}
ABSTRACTIn the present study, a one-dimensional governing equation with a vertical acceleration term is used to analyse the free surface profile of various types of jumps. Initially, the surface profile of various types of jumps are reproduced analytically by using a suitable eddy diffusivity term. The approximations of the surface profile for various jumps are then verified numerically. Based on the comparisons, an empirical relationship between the Froude number and the turbulent diffusivity coefficient is established. The proposed empirical relationship is used in the governing equation to compute the various jumps, where an implicit two dimensional flow is assumed. The obtained results are compared with the experimental data to assure the transition of flow from undular jump to breaking jump. The comparisons of numerical results of wave profiles, pressure distribution, wave length and wave amplitude with the existing experimental data for various Froude numbers indicated the suitability of the proposed empirical relationship. Finally, the transitions of flow from undular jump to breaking hydraulic jump are discussed.Keywords: Froude numberhydraulic jumpopen channel flowsurface profileundular jump
期刊介绍:
The Journal of Hydraulic Research (JHR) is the flagship journal of the International Association for Hydro-Environment Engineering and Research (IAHR). It publishes research papers in theoretical, experimental and computational hydraulics and fluid mechanics, particularly relating to rivers, lakes, estuaries, coasts, constructed waterways, and some internal flows such as pipe flows. To reflect current tendencies in water research, outcomes of interdisciplinary hydro-environment studies with a strong fluid mechanical component are especially invited. Although the preference is given to the fundamental issues, the papers focusing on important unconventional or emerging applications of broad interest are also welcome.