Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena最新文献

{"title":"TAYLOR-COUETTE-POISEUILLE FLOWS: FROM RANS TO LES","authors":"Christophe Friess, Sébastien Poncet, S. Viazzo","doi":"10.1615/tsfp8.1700","DOIUrl":"https://doi.org/10.1615/tsfp8.1700","url":null,"abstract":"The present paper proposes a study of a Taylor-Couette-Poiseuille flow in a narrow gap between a rotor and a stator, using two different rotation rates. Refined Large-Eddy Simulation results, using the WALE model Nicoud & Ducros (1999), hold for reference data, whereas the efficiency of a RANS model, the Elliptic Blending Reynolds Stress Model (EB-RSM) (Manceau & Hanjali, 2002; Manceau, 2005), and a hybrid RANS/LES method, the so-called \"Equivalent DES\" (Manceau et al., 2010; Friess & Manceau, 2012) is studied.","PeriodicalId":206337,"journal":{"name":"Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena","volume":"51 10","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120850498","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}

{"title":"ON MULTISCALE ACCELERATION STATISTICS IN ROTATING AND SHEARED HOMOGENEOUS TURBULENCE","authors":"F. Jacobitz, K. Schneider, W. Bos, M. Farge","doi":"10.1615/tsfp8.820","DOIUrl":"https://doi.org/10.1615/tsfp8.820","url":null,"abstract":"","PeriodicalId":206337,"journal":{"name":"Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena","volume":"37 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116791394","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}

{"title":"NAVIER-STOKES SIMULATION WITH FLUID PARTICLES LOCATION UNCERTAINTY","authors":"S. Harouna, É. Mémin","doi":"10.1615/tsfp8.900","DOIUrl":"https://doi.org/10.1615/tsfp8.900","url":null,"abstract":"","PeriodicalId":206337,"journal":{"name":"Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127068830","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}

{"title":"INVESTIGATION OF WING STALL DELAY EFFECT DUE TO AN UNDULATING LEADING EDGE: AN LES STUDY","authors":"A. Skillen, A. Revell, J. Favier, A. Pinelli, U. Piomelli","doi":"10.1615/tsfp8.1960","DOIUrl":"https://doi.org/10.1615/tsfp8.1960","url":null,"abstract":"We present LES simulations of the flow over a wing with sinusoidal leading edge undulations. The undulations act as a passive flow control device, offering superior poststall aerodynamic performance relative to the unmodified wing with the same mean chord. The baseline case of a regular wing is also presented for comparison. In all cases the Reynolds number based on bulk velocity and mean chord is equal to 120,000, and the angle of attack is set to 20◦. The study explores the details of the flow physics and the mechanisms by which the post-stall aerodynamic benefit is gained. For the particular set of geometrical and aerodynamic parameters considered, a hitherto unreported physical mechanism by which the undulation offers their benefit is observed. This increased understanding of the flow physics for the current configuration is an important step towards a more general understanding and the incorporation of the technology into practical designs. Potential applications include vertical axis wind turbines, unmanned air vehicles, helicopter blades, and canard surfaces; the present Reynolds number is of particular relevance to the first two of these applications. Introduction Inspired by the high maneuverability of the humpback whale, there has been a surge in interest in the mammal’s hydrodynamic performance, with a view towards capitalising on findings in the field of biomimetics. A key contributing factor to this high maneuverability is the form of the pectoral flippers; specifically the presence of protuberances A","PeriodicalId":206337,"journal":{"name":"Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena","volume":"217 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133678522","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}

{"title":"FLOW SOURCES OF WALL PRESSURE FLUCTUATIONS RESOLVED BY DDES IN A REATTACHING FLOW REGION","authors":"T. T. Tran, R. Perrin, R. Manceau, J. Borée, P. Jordan","doi":"10.1615/tsfp8.1160","DOIUrl":"https://doi.org/10.1615/tsfp8.1160","url":null,"abstract":"This paper is concerned with the analysis of the flow structures responsible for the wall pressure fluctuations predicted by DDES near a reattachment. To this aim, a simulation of the flow over a thick plate is considered. It observed that the linear part of sources is dominant upstream of the reattachment, and that quadratic sources dominate downstream. This is associated with the rapid loss of coherence of the vortices shed from the separated shear layer in the downstream region. Furthermore, it is shown that linear stochastic estimation of the velocity field from the wall pressure well reproduce the linear sources, with negligible quadratic sources.","PeriodicalId":206337,"journal":{"name":"Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena","volume":"86 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134256451","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}

{"title":"ANALYSIS OF THE EFFECTS OF ROTATION ON AN AXISYMMETRIC WALL JET","authors":"R. Manceau, R. Perrin, M. Hadžiabdić, P. Fourment, S. Benhamadouche","doi":"10.1615/tsfp8.810","DOIUrl":"https://doi.org/10.1615/tsfp8.810","url":null,"abstract":"The case of a turbulent round jet impinging perpendicularly onto a rotating, heated disc is investigated, aiming at understanding the mechanisms at the origin of the influence of rotation on the radial wall jet and associated heat transfer. The present study is based on the complementary use of an analysis of the order of magnitudes of the terms of the mean momentum and Reynolds stress transport equations, available experiments and dedicated Reynolds-Averaged Navier–Stokes (RANS) computations with refined turbulence models. The analysis identifies a scenario for the appearance of rotational effects when the rotation rate is gradually increased.","PeriodicalId":206337,"journal":{"name":"Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena","volume":"96 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127778308","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}

{"title":"A NOTE ON LOCAL ISOTROPY CRITERIA IN SHEAR FLOWS WITH COHERENT MOTION","authors":"F. Thiesset, L. Danaila, R. Antonia","doi":"10.1615/tsfp8.1980","DOIUrl":"https://doi.org/10.1615/tsfp8.1980","url":null,"abstract":"Whilst Local Isotropy (LI) is widely used, it is also necessary to test its validity, especially in shear flows, characterized by large-scale anisotropy. Important questions are whether the small scales are isotropic and how their properties depend on large-scale parameters (mean shear, the shear induced by a coherent motion, the Reynolds number etc.). We focus on two families of LI tests: i) classical, kinematic tests, in which time-averages are compared to their isotropic values. The large-scale parameters do not appear explicitly. We only use here one example of such tests. ii) Phenomenological tests, which explicitly account for the large-scale strain, as well as its associated dynamics. In flows populated by coherent motions in which phaseaverages are pertinent for describing the flow dynamics, we propose a Local Isotropy (LI) criterion based on the intensity of the turbulent strain rate at a given scale~r and a particular phase φ , sφ (~r,φ). The formulation is the following: ”If LI were to be valid at a vectorial scale~r and a phase φ , then the intensity of the turbulent strain rate sφ (~r,φ) should prevail over the combined effect of the mean shear S and of the shear S̃ associated with the coherent motion”. The mathematical expression of sφ (~r,φ) depends on the Laplacian of the total kinetic energy second-order structure function. Therefore, the proposed expression allows the eventual anisotropy to be taken into account. The new LI criterion is used together with data taken in the intermediate wake behind a circular cylinder. It is highlighted that (i) when S+ S̃ is important, LI only holds for scales smaller than the Taylor microscale (ii) when S+ S̃ is small, the domain in which LI is valid extends up to the largest scales. INTRODUCTION Local isotropy (LI) is seemingly one of the most important hypotheses on small-scale statistics. LI was first enunciated by Kolmogorov (1941), and further utilized and sometimes tested, in most of the laboratory flows. From the analytical viewpoint, LI leads to simplified expressions of e.g. the total kinetic energy, the dissipation rate of kinetic energy or scalar variance, structure functions at a given scale. Simple expressions of statistics are useful for the experimentalists, because of the limited possibilities to measure all the velocity components, as well as their spatial distribution. Although LI is extensively used, it is nonetheless necessary to test its validity, especially in shear flows, characterized by large-scale anisotropy. Important questions are whether the small scales are isotropic and if there is a clear dependence of their statistics on large-scale parameters (mean shear S, the shear induced by a coherent motion S̃, the Reynolds number etc.). Using a compilation of experimental and numerical data, Schumacher et al. (2003) showed that LI prevails for small values of the ratio S/Rλ (Rλ is the Taylor microscale Reynolds number). One should expect that the magnitude of the shear wi","PeriodicalId":206337,"journal":{"name":"Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121953624","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}

{"title":"AMPLITUDE AND FREQUENCY MODULATION OF THE SMALL SCALES IN A TURBULENT JET","authors":"D. Fiscaletti, G. Elsinga, B. Ganapathisubramani, J. Westerweel","doi":"10.1615/tsfp8.2190","DOIUrl":"https://doi.org/10.1615/tsfp8.2190","url":null,"abstract":"This work involves the large-scale amplitude and frequency modulation of the small-scale motions in fullydeveloped turbulence of a high Reynolds number jet. The scales responsible for the production of turbulent kinetic energy (large scales), and those responsible for its viscous dissipation (small scales) are extracted from time series of hotwire signals, using a band-pass spectral filter. The top-down interaction between the turbulent scales is then examined. We show that the strength of the large-scale fluctuations affect non-linearly the amplitude of the small-scale signal. Furthermore, the higher frequency components within the small-scale signal exhibit stronger amplitude modulation, which evidences frequency modulation. Analogies and dissimilarities with turbulent flows other than jets are discussed.","PeriodicalId":206337,"journal":{"name":"Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116546372","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}

{"title":"ON THE ERGODICITY OF GRID TURBULENCE","authors":"L. Djenidi, S. Tardu, R. Antonia","doi":"10.1615/tsfp8.1040","DOIUrl":"https://doi.org/10.1615/tsfp8.1040","url":null,"abstract":"","PeriodicalId":206337,"journal":{"name":"Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115078557","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}

{"title":"HYBRID RANS/LES SIMULATIONS OF A CAVITATING FLOW IN VENTURI","authors":"J. Decaix, E. Goncalvès","doi":"10.1615/tsfp8.1560","DOIUrl":"https://doi.org/10.1615/tsfp8.1560","url":null,"abstract":"","PeriodicalId":206337,"journal":{"name":"Proceeding of Eighth International Symposium on Turbulence and Shear Flow Phenomena","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-08-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131064165","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}