Fully-developed Turbulent Pipe Flow Using a Zero-Equation Model

Autor:	Khalid N. Alammar
Rok vydání:	2013
Předmět:	Hydrodynamic stability General Computer Science K-epsilon turbulence model Turbulence General Engineering Reynolds number Magnetic Reynolds number Geometry Reynolds stress Mechanics Reynolds equation Physics::Fluid Dynamics symbols.namesake Reynolds decomposition symbols Mathematics
Zdroj:	Research Journal of Applied Sciences, Engineering and Technology. 6:687-690
ISSN:	2040-7467 2040-7459
DOI:	10.19026/rjaset.6.4181
Popis:	Aim of this study is to evaluate a zero-equation turbulence model. A fully-developed turbulent pipe flow was simulated. Uncertainty was approximated through grid-independence and model validation. Results for mean axial velocity, u + and Reynolds stress had maximum error of 5%, while results for the friction factor had negligible error. The mean axial velocity was shown to increase and extend farther in the outer layer with increasing Reynolds number, up to 10 6 . There was no effect of Reynolds number on u + below wall distance, Y + , of 100. Similar to the friction velocity, peak of the Reynolds stress was shown to increase and extend farther in the outer layer with increasing Reynolds number. There was no effect of Reynolds number on Reynolds stress below wall distance of 20. The new turbulence model is equally applicable to developing and external flows using the same constant. For wall- bounded flows, the constant is a function of wall roughness.
Databáze:	OpenAIRE
Externí odkaz:	https://explore.openaire.eu/search/publication?articleId=doi_________::8c07b54a6f9e1246209b2e004726b996 https://doi.org/10.19026/rjaset.6.4181 Zobrazit plný text záznamu