Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena最新文献_第7页

PLASMA-BASED MANIPULATION OF SECONDARY FLOW TOWARDS PRESSURE RECOVERY ENHANCEMENT IN A 3D DIFFUSER: A COMPUTATIONAL STUDY 三维扩散器中二次流的等离子体操纵:一项计算研究

Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena Pub Date : 1900-01-01 DOI: 10.1615/tsfp8.1720

I. Maden, R. Maduta, S. Jakirlic, S. Grundmann, C. Tropea, J. Eaton

引用次数: 0

EFFECTS OF RADIATIVE HEAT TRANSFER ON THE TURBULENCE STRUCTURE IN REACTING AND INERT MIXING LAYERS 辐射传热对反应层和惰性混合层湍流结构的影响

Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena Pub Date : 1900-01-01 DOI: 10.1615/tsfp8.740

Somnath Ghosh, R. Friedrich, C. Stemmer, B. Cuenot, M. Hafi

引用次数: 0

VERY-LARGE-SCALE MOTIONS IN A TURBULENT CHANNEL FLOW 紊流沟道中非常大规模的运动

Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena Pub Date : 1900-01-01 DOI: 10.1615/tsfp8.40

Jin Lee, Jae Hwa Lee, Jung‐Il Choi, H. Sung

引用次数: 0

ODTLES SIMULATIONS OF TURBULENT FLOWS THROUGH HEATED CHANNELS AND DUCTS 通过加热通道和管道的湍流模拟

Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena Pub Date : 1900-01-01 DOI: 10.1615/tsfp8.760

C. Glawe, F. Schulz, E. Gonzalez-Juez, H. Schmidt, A. Kerstein

{"title":"ODTLES SIMULATIONS OF TURBULENT FLOWS THROUGH HEATED CHANNELS AND DUCTS","authors":"C. Glawe, F. Schulz, E. Gonzalez-Juez, H. Schmidt, A. Kerstein","doi":"10.1615/tsfp8.760","DOIUrl":"https://doi.org/10.1615/tsfp8.760","url":null,"abstract":"A widely occurring problem in fluid dynamics either in engineering or e.g. hydrology is the turbulent transport through channels and ducts. ODTLES, a stochastic based multi-scale and multi-dimensional model, is a promising tool to describe these flows even including scalar properties like temperature. We are quantifying the ability of ODTLES to describe the heated channel flow with respect to the Prandtl number and the flow through squared ducts with respect to the Reynolds number. INTRODUCTION An interesting challenge in classical mechanics is the description of a turbulent fluid. A key difficulty in modelling these flows is their multi-scale nature. Even fundamental problems like the flow through a channel or duct are still under study and have been investigated by several groups in experiments (e.g. Hirota et al. (1997)) and numerical studies (e.g. Kawamura et al. (1999), Pinelli et al. (2010)). Direct Numerical Simulations (DNSs) are widely used to investigate these fundamental problems because they are solving the governing physical incompressible Navier-Stokes equations without assumptions. So DNSs can yield the complex statistics of moderate Reynolds number channel and duct flows, but are limited mostly to fundamental research due to the wide range of spatial and temporal scales emerging in technical and meteorological flows. These problems are for example treated by modeling small scales in Large-Eddy-Simulations (LES). These models have issues in resolving non-isotropic flow regions (e.g. near wall and stratified flows) and turbulent backscatter effects. The disagreement in the scientific community about the influence of the latter effects (e.g. Piomelli et al. (1991)) indicates the lack of understanding. Figure 1. Coordinate system and geometry of the duct (left) and the channel (right). From this point of view, stochastic approaches based on One-Dimensional-Turbulence (ODT) (e.g. Kerstein et al. (2001), Kerstein (1999)) and multi-dimensional approaches incorporating ODT, like ODTLES (e.g. Schmidt et al. (2008) and Gonzalez-Juez et al. (2011)), are an interesting alternative. The ability of ODT to resolve molecular effects (as DNSs) and to describe even non isotropic 3D turbulence using a stochastic process distinguishes ODT and ODTLES from techniques such as LES and ReynoldsAveraged-Navier-Stokes (RANS) models. NUMERICAL METHODOLOGY We are considering incompressible flows in a channel and a duct (see fig. 1). The square duct is bounded by walls at the faces normal to x3 = {−h,h} and x2 = {−h,h}, the channel by walls at x2 = {0,2h}. All other boundary conditions are considered periodic to mimic e.g. an infinite streamwise extension in the x1-direction. The turbulent channel can be described by both ODT and ODTLES, the square duct only by ODTLES due to the three dimensional non turbulent properties (e.g. secondary instabilities) of the characteristic flow. To understand the approach of ODTLES, a brief description of ODT will follow first","PeriodicalId":206337,"journal":{"name":"Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena","volume":"63 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131249437","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 10

PERTURBING SPANWISE MODES IN TURBULENT BOUNDARY LAYERS 湍流边界层中的扰动展向模态

Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena Pub Date : 1900-01-01 DOI: 10.1615/tsfp8.1340

Shaokai Zheng

引用次数: 3

SPANWISE OSCILLATORY WALL MOTION IN CHANNEL FLOW: DRAG-REDUCTION MECHANISMS INFERRED FROM DNS-PREDICTED PHASE-WISE PROPERTY VARIATIONS AT Reτ = 1000 通道流动中的横向振荡壁面运动:从dns预测的Reτ = 1000时的相位特性变化推断出的减阻机制

Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena Pub Date : 1900-01-01 DOI: 10.1615/tsfp8.1310

L. Agostini, E. Touber, M. Leschziner

引用次数: 39

THE ROLE OF THE HAIRPIN VORTEX SOLUTION ON LAMINAR-TURBULENT TRANSITION OF PLANE COUETTE FLOW AT MODERATE REYNOLDS NUMBER 中等雷诺数下发夹涡解在平面couette流层流-湍流过渡中的作用

Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena Pub Date : 1900-01-01 DOI: 10.1615/tsfp8.2050

T. Itano, S. Generalis, Takahiro Ninomiya, M. Sugihara-Seki

引用次数: 0

TURBULENCE MODIFICATION BY PARTICLES IN A HORIZONTAL CHANNEL FLOW 水平通道流动中粒子对湍流的影响

Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena Pub Date : 1900-01-01 DOI: 10.1615/tsfp8.1590

G. F. Tay, D. Kuhn, M. Tachie

引用次数: 0

DNS OF TURBULENT DRAG REDUCTION BY SPANWISE WALL FORCING: THE REYNOLDS NUMBER EFFECT 沿展向壁面强迫减少湍流阻力的DNS:雷诺数效应

Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena Pub Date : 1900-01-01 DOI: 10.1615/tsfp8.1330

Yongmann M. Chung, E. Hurst, Q. Yang

引用次数: 1

OFF-WALL BOUNDARY CONDITIONS FOR TURBULENT SIMULATIONS FROM MINIMAL FLOW UNITS IN TRANSITIONAL BOUNDARY LAYERS 过渡边界层最小流动单元湍流模拟的壁外边界条件

Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena Pub Date : 1900-01-01 DOI: 10.1615/tsfp8.1480

R. García-Mayoral, B. Pierce, J. Wallace

{"title":"OFF-WALL BOUNDARY CONDITIONS FOR TURBULENT SIMULATIONS FROM MINIMAL FLOW UNITS IN TRANSITIONAL BOUNDARY LAYERS","authors":"R. García-Mayoral, B. Pierce, J. Wallace","doi":"10.1615/tsfp8.1480","DOIUrl":"https://doi.org/10.1615/tsfp8.1480","url":null,"abstract":"A reduced order model for off-wall boundary conditions for turbulent flows is proposed. The model circumvents the need to resolve the buffer layer near the wall by providing conditions directly above it for the overlying flow. The effect of the buffer layer is modeled as a pattern of periodic blocks similar to the minimal unit of Jimenez & Moin (1991). The model is reduced to the imprint of such blocks on a plane at y+ ≈ 100, at which Dirichlet boundary conditions are imposed for the rest of the flow. Blocks are constructed from a variety of canonical flows, from low-Reynolds-number turbulent channels to the transitional-boundary-layer direct simulation of Sayadi et al. (2012). The block sizes are selected so that they are statistically representative of fully turbulent flow, and so that they contain the dominant structures at y+ ≈ 100, as educed from direct mode decomposition. The model has the form of a collection of Fourier modes in space and time, and comprises ∼1% of the parameters necessary to describe the full flow field at the plane considered, while it reproduces ∼90% of the amplitudes of the flow statistics. The simulations conducted with these modeled off-wall boundary conditions correctly reproduce the turbulent statistics of the overlying flow.","PeriodicalId":206337,"journal":{"name":"Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115566661","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 2