{"title":"A method for coarse graining fluctuation velocities in granular flows","authors":"Neiladri S. Ray, Devang Khakhar","doi":"10.1007/s10035-023-01338-7","DOIUrl":null,"url":null,"abstract":"<div><p>The granular temperature, which is the mean kinetic energy per unit mass of velocity fluctuations, is an important rheological parameter for granular flows. Artoni and Richard (Phys Rev E 91: 032202, 2015) showed that accurate calculation of the fluctuation velocity during coarse graining requires the subtraction of the mean velocity at the position of the particle since the variation of the mean velocity over the coarse graining domain may be of the same order as the fluctuation velocity. This requires a two-step calculation. In this study, a single-step method of calculating granular temperatures is proposed. The values obtained by this method for a simulated system of inclined surface flow of granular materials are compared with those obtained using earlier methods and are shown to be accurate.</p></div>","PeriodicalId":582,"journal":{"name":"Granular Matter","volume":"25 3","pages":""},"PeriodicalIF":2.3000,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://link.springer.com/content/pdf/10.1007/s10035-023-01338-7.pdf","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Granular Matter","FirstCategoryId":"5","ListUrlMain":"https://link.springer.com/article/10.1007/s10035-023-01338-7","RegionNum":3,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"MATERIALS SCIENCE, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 0
Abstract
The granular temperature, which is the mean kinetic energy per unit mass of velocity fluctuations, is an important rheological parameter for granular flows. Artoni and Richard (Phys Rev E 91: 032202, 2015) showed that accurate calculation of the fluctuation velocity during coarse graining requires the subtraction of the mean velocity at the position of the particle since the variation of the mean velocity over the coarse graining domain may be of the same order as the fluctuation velocity. This requires a two-step calculation. In this study, a single-step method of calculating granular temperatures is proposed. The values obtained by this method for a simulated system of inclined surface flow of granular materials are compared with those obtained using earlier methods and are shown to be accurate.
期刊介绍:
Although many phenomena observed in granular materials are still not yet fully understood, important contributions have been made to further our understanding using modern tools from statistical mechanics, micro-mechanics, and computational science.
These modern tools apply to disordered systems, phase transitions, instabilities or intermittent behavior and the performance of discrete particle simulations.
>> Until now, however, many of these results were only to be found scattered throughout the literature. Physicists are often unaware of the theories and results published by engineers or other fields - and vice versa.
The journal Granular Matter thus serves as an interdisciplinary platform of communication among researchers of various disciplines who are involved in the basic research on granular media. It helps to establish a common language and gather articles under one single roof that up to now have been spread over many journals in a variety of fields. Notwithstanding, highly applied or technical work is beyond the scope of this journal.