{"title":"Numerical Simulations of Turbulent Gas-solid Flow in a Gradual Expansion","authors":"A. Benavides-Moran, S. Lain","doi":"10.47176/jafm.17.05.2340","DOIUrl":null,"url":null,"abstract":"Modeling efforts on turbulent gas-solid flows have mainly focused on studying particle-laden flows in channels and pipes. Despite its significance for industrial applications, the study of gas-solid flows in sudden or gradual expansions is less common in the literature. This paper challenges current two-phase flow models to compute the dilute turbulent gas-solid flow in a vertically oriented 12° conical diffuser. The solids phase is modeled in two ways: the Two-Fluid Model approach that incorporates closure relations derived from the kinetic theory of granular flow, and the Euler-Lagrange particle tracking model with two-way coupling. In both cases, turbulence in the gas phase is estimated by the Reynolds stress model with additional modulation terms that account for the effect of the particles on the gas-phase turbulence. Simulation results are validated versus experimental benchmark data not only for gas axial velocity but also for streamwise and radial turbulence intensity, as comparison with such turbulent variables has not been detailed in previous studies. Nevertheless, due to the lack of experimental data for validation, profiles of solids axial velocity are only compared numerically. Contours of turbulence kinetic energy and granular temperature in the diffuser region reveal a high shear area responsible for the production of turbulence in both phases. Moreover, results obtained from the Euler-Lagrange model show an intense particle fluctuating velocity in the streamwise direction downstream of the diffuser.","PeriodicalId":49041,"journal":{"name":"Journal of Applied Fluid Mechanics","volume":null,"pages":null},"PeriodicalIF":1.1000,"publicationDate":"2024-05-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Journal of Applied Fluid Mechanics","FirstCategoryId":"5","ListUrlMain":"https://doi.org/10.47176/jafm.17.05.2340","RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q4","JCRName":"MECHANICS","Score":null,"Total":0}
引用次数: 0
Abstract
Modeling efforts on turbulent gas-solid flows have mainly focused on studying particle-laden flows in channels and pipes. Despite its significance for industrial applications, the study of gas-solid flows in sudden or gradual expansions is less common in the literature. This paper challenges current two-phase flow models to compute the dilute turbulent gas-solid flow in a vertically oriented 12° conical diffuser. The solids phase is modeled in two ways: the Two-Fluid Model approach that incorporates closure relations derived from the kinetic theory of granular flow, and the Euler-Lagrange particle tracking model with two-way coupling. In both cases, turbulence in the gas phase is estimated by the Reynolds stress model with additional modulation terms that account for the effect of the particles on the gas-phase turbulence. Simulation results are validated versus experimental benchmark data not only for gas axial velocity but also for streamwise and radial turbulence intensity, as comparison with such turbulent variables has not been detailed in previous studies. Nevertheless, due to the lack of experimental data for validation, profiles of solids axial velocity are only compared numerically. Contours of turbulence kinetic energy and granular temperature in the diffuser region reveal a high shear area responsible for the production of turbulence in both phases. Moreover, results obtained from the Euler-Lagrange model show an intense particle fluctuating velocity in the streamwise direction downstream of the diffuser.
期刊介绍:
The Journal of Applied Fluid Mechanics (JAFM) is an international, peer-reviewed journal which covers a wide range of theoretical, numerical and experimental aspects in fluid mechanics. The emphasis is on the applications in different engineering fields rather than on pure mathematical or physical aspects in fluid mechanics. Although many high quality journals pertaining to different aspects of fluid mechanics presently exist, research in the field is rapidly escalating. The motivation for this new fluid mechanics journal is driven by the following points: (1) there is a need to have an e-journal accessible to all fluid mechanics researchers, (2) scientists from third- world countries need a venue that does not incur publication costs, (3) quality papers deserve rapid and fast publication through an efficient peer review process, and (4) an outlet is needed for rapid dissemination of fluid mechanics conferences held in Asian countries. Pertaining to this latter point, there presently exist some excellent conferences devoted to the promotion of fluid mechanics in the region such as the Asian Congress of Fluid Mechanics which began in 1980 and nominally takes place in one of the Asian countries every two years. We hope that the proposed journal provides and additional impetus for promoting applied fluids research and associated activities in this continent. The journal is under the umbrella of the Physics Society of Iran with the collaboration of Isfahan University of Technology (IUT) .