Numerical simulation of flow with large eddy simulation at Re = 3900

Abstract

Purpose Over the past few decades, the flow around circular cylinders has been one of the highly researched topics in the field of offshore engineering and fluid-structure interaction (FSI). In the current study, numerical simulations for flow around a fixed circular cylinder are performed at Reynolds number (Re) = 3900 with the LES method using the ICEM-CFD and ANSYS Fluent tool for meshing and analysis, respectively. Previously, similar studies have been conducted at the same Reynolds number, but there have been discrepancies in the results, particularly in calculating the recirculation length and angle of separation. In addition, the purpose of this study is to address the impact of time interval averaging to obtain the fully converged solution. Design/methodology/approach This study presents the LES method, using the ICEM-CFD and ANSYS fluent tool for meshing and analysis. Findings In the current study, turbulence statistics are sampled for 25, 50, 75 and 100 vortex-shedding cycles with the CFL value O (1). The recirculation length, angle of separation, hydrodynamic coefficients and the wake behind the cylinder are investigated up to ten diameters. The drag coefficient and Strouhal number are observed to be less sensitive, whereas the recirculation length appeared to be highly dependent on the average time statistics and the non-dimensional time step. Similarly, the mean streamwise and cross-flow velocity are observed to be sensitive to the average time statistics and non-dimensional time step in the wake region near the cylinder. Originality/value In the current investigation, turbulence statistics are sampled for 25, 50, 75 and 100 vortex-shedding cycles with the CFL value O (1), using large eddy simulation method at Re = 3900 around a circular cylinder. The impact of time interval averaging to obtain the fully converged mean flow field is addressed. No such consideration is yet published in the literature.

Application Effect Analysis of the Mie Scattering Theory Based on Big Data Analysis Technology in the Optical Scattering Direction

“…The number of bubbles in the wake is huge and their diameters are different. Among them, large bubbles will rise quickly, break, and disappear, while small bubbles can survive in seawater for more than ten minutes or even dozens of minutes [2]. Due to the obvious difference of bubble density, compressibility, and other parameters from seawater and the influence of turbulence in the wake, the bubble distribution in the wake is uneven, which leads to the obvious difference between the transmis-sion characteristics of sound wave and light wave in the wake and that in seawater.…”

Numerical investigation of the effect of spanwise length and mesh density on flow around cylinder at Re = 3900 using LES model

“…In all these case studies, number of elements on cylinder circumference (N c ) × number of elements on cylinder in radial direction (N R ) are 240×60 respectively. 240x60 is taken from the study of Khan et al [7], who concluded that reduction in number of circumferential and radial nodes will overestimate the value of C d , reduction in recirculation length, and a delay in flow separation.…”

“…The flow around a fixed cylinder at Re = 3900 come under the lower subcritical flow regime, which is highly sensitive in terms of flow separation, boundary layer nature, recirculation length, wake characteristics, and other hydrodynamic coefficients [3]. The availability of large-scale experimental and numerical data [4][5][6][7][8][9][10] for the flow around cylinders at Re = 3900 makes it an excellent benchmark case for assessing the capability of computational tools and process.…”

“…The aim of this paper is to use a benchmark problem to compare the performance of the Open FOAM sub grid model quantitatively, as well as to address some key factors that affect predictive performance. Korinek et al [7] used LES code and the Smagorinsky-Lilly subgrid-scale model to identify the effect of spanwise length and mesh resolution on measuring recirculation length and angle of separation around a fixed structure at Reynolds number = 3900. Most recently, Korinek et al [9] used partially average NS-bridging technique to investigate the flow over same Reynolds number at different ratio of resolved and unresolved turbulent kinetic energy.…”

Numerical simulation for transient flow of Williamson fluid with multiple slip model in the presence of chemically reacting species

“…The MHD flow and heat transfer characteristics past a permeable stretching sheet have been studied analytically by Hayat et al (2011). Enormous research works (Ullaha et al, 2017;Sheikh and Abbas, 2015;Hayat et al, 2017a;AnkiReddy and Das, 2016;Hayat et al, 2017b;Turkyilmazoglu, 2018aTurkyilmazoglu, , 2018bKhan et al, 2019aKhan et al, , 2019bKhan et al, , 2019cKhan et al, , 2019dHayat et al, 2016;Turkyilmazoglu, 2017) have been done on the MHD flow of heat and mass transfer over a stretching surface under different physical situations.…”