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

{"title":"SPATIAL CORRELATION OF VELOCITY AND HEAT TRANSFER DOWNSTREAM OF A BACKWARD FACING STEP USING 2D-3C PIV AND IR THERMOGRAPHY","authors":"S. Yamada, Hajime Nakamura","doi":"10.1615/tsfp9.610","DOIUrl":"https://doi.org/10.1615/tsfp9.610","url":null,"abstract":"","PeriodicalId":196124,"journal":{"name":"Proceeding of Ninth International Symposium on Turbulence and Shear Flow Phenomena","volume":"5 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":"123894018","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":"3D DNS OF METHANE-AIR TURBULENT PREMIXED FLAME IN THIN REACTION ZONES WITH A DETAILED KINETIC MECHANISM","authors":"Basmil Yenerdag, Y. Naka, M. Shimura, M. Tanahashi","doi":"10.1615/tsfp9.160","DOIUrl":"https://doi.org/10.1615/tsfp9.160","url":null,"abstract":"","PeriodicalId":196124,"journal":{"name":"Proceeding of Ninth International Symposium on Turbulence and Shear Flow Phenomena","volume":"31 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":"127056058","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 A TURBULENT FLOW FROM THE TRANSITIONALLY ROUGH REGIME TO THE FULLY ROUGH REGIME","authors":"L. Chan, M. MacDonald, N. Hutchins, D. Chung, A. Ooi","doi":"10.1615/tsfp9.250","DOIUrl":"https://doi.org/10.1615/tsfp9.250","url":null,"abstract":"Direct Numerical Simulations (DNS) are carried out in a turbulent rough-wall pipe at low and medium Reynolds numbers. The rough surface, which is comprised of threedimensional sinusoidal roughness elements, was viscously scaled from the transitionally rough regime to the fully rough regime. The main aim of this study is to analyse the behaviour of the near-wall cycle as the surface condition changes from smooth through to fully rough. When analysing the streamwise velocity, a triple decomposition is used to distinguish between the fluctuations due to the spatial variation with the actual turbulent fluctuations. For small roughness height (h+ < 15), the near-wall cycle streaks occurs above the roughness elements. Although the high and low speed streaks look similar to the smooth wall when visually inspected, subtle differences are observed when the premultiplied energy spectra are analysed. When the flow is fully rough, the near-wall cycle is replaced by the stationary features of the flow which dominate within the roughness elements. We also analyse the contribution of the apparent wall shear stress due to form (pressure) drag (τR) expressed as a ratio between form and total shear stress (Rτ = τR τT ). In the fully rough regime, the form drag dominates (Rτ > 0.75) and disrupts the near-wall cycle. Townsend’s outer layer similarity is observed when the wall normal height normalised by the mean radius of the pipe y/R0 is greater than 0.56, where a collapse in the streamwise premultiplied energy spectra is obtained.","PeriodicalId":196124,"journal":{"name":"Proceeding of Ninth International Symposium on Turbulence and Shear Flow Phenomena","volume":"137 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":"122437184","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":"ACTIVE SEPARATION CONTROL PROCESS OVER A SHARP EDGE RAMP","authors":"A. Debien, S. Aubrun, N. Mazellier, A. Kourta","doi":"10.1615/tsfp9.580","DOIUrl":"https://doi.org/10.1615/tsfp9.580","url":null,"abstract":"","PeriodicalId":196124,"journal":{"name":"Proceeding of Ninth International Symposium on Turbulence and Shear Flow Phenomena","volume":"37 2","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1900-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132433012","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":"LARGE-EDDY SIMULATION OF SPRAY COMBUTION IN A SECTOR COMBUSTOR FOR REGIONAL JET AIRCRAFT ENGINE - EFFECT OF DOUBLE-WALL LINER ON NOx FORMATION -","authors":"H. Moriai, K. Hori, R. Kurose, S. Komori","doi":"10.1615/tsfp9.340","DOIUrl":"https://doi.org/10.1615/tsfp9.340","url":null,"abstract":"Large-eddy simulation (LES) is applied to a turbulent spray combustion field in a sector combustor for a regional jet aircraft engine under development, and the effects of liner-cooling air flow outlet location (i.e., effect of single/double wall liners) on the combustion behaviour and NOx emission are investigated. The combustor is designed based on RQL (Rich burn, Quick quench, Lean burn) concept to reduce NOx emission. In the LES, Jet-A1 is used as liquid fuel, and individual droplet motion is tracked in a Lagrangian manner with a parcel model. As the turbulent combustion model, an extended flamelet/progress-variable approach, in which heat transfer between droplets and ambient gas including radiation and heat loss from walls can be taken into account, is employed. A detailed chemistry mechanism of Jet-A1 with 1537 reactions and 274 chemical species is used. The radiative heat transfer is computed by the discrete ordinate (DO) method. The LES results show general agreement with the experimental data, and the double wall liner design seems desirable for low NOx RQL combustor. INTRODUCTION Due to increasing environmental awareness worldwide, aircraft emission (NOx, CO, PM, etc.) control have become more stringent in recent years. The aircraft exhaust gas amount is severely limited by the regulations adopted by CAEP (Committee on Aviation Environmental Protection). By CAEP/6 regulations which came into effect in 2008, NOx emission is reduced by 12% and by CAEP/8 regulations which will come into effect in 2014 NOx will be reduced by further 15%. NOx regulation is expected to be more stringent in the future steadily (Moriai and Miyake, 2008). With this background, the low NOx combustor technology is very important in the development of the latest aircraft engines. However, the precise predictions of emission from the combustor including combustion characteristics are so difficult that the development cycles including hardware design, fabricating and evaluation tests are generally repeated many times to meet specification requirements and end up with huge cost and time. Therefore, if many hardware tests are substituted with numerical simulations, significant development cost reduction is possible. Because the internal flow of the combustor is composed of complex phenomena, including spray atomization, turbulent mixing, and chemical reactions, numerical simulation is very difficult. In recent years, LES (Large-eddy simulation) that can simulate unsteady turbulent flow well attracts attention. The purpose of this study is, therefore, to apply the LES to a turbulent spray combustion field in a sector combustor for a regional jet aircraft engine under development, and to predict the spray combustion behaviour and emissions such as NOx and soot. Special attentions are focused on the effect of liner-cooling air flow outlet location (i.e., effect of single/double wall liner designs) on the NOx emission. NUMERICAL METHODS Large-Eddy Simulation In this work,","PeriodicalId":196124,"journal":{"name":"Proceeding of Ninth International Symposium on Turbulence and Shear Flow Phenomena","volume":"1 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":"131065448","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 DNS BASED ANALYSIS OF NOISE GENERATION BY A TURBULENT PREMIXED FLAME","authors":"A. Haghiri, M. Talei, M. Brear, E. Hawkes","doi":"10.1615/tsfp9.140","DOIUrl":"https://doi.org/10.1615/tsfp9.140","url":null,"abstract":"Direct numerical simulation (DNS) is used to study sound generation by an unconfined, turbulent premixed flame. The computational grid is set up such that both the near and far fields are fully resolved, and simple chemistry is used to reduce the computational cost. In keeping with earlier, simpler studies by the group, flame annihilation events are again observed as strong monopolar sources of sound, and their amplitudes are consistent with the groups previously published scalings. Analysis of the radiated sound then shows broadband spectra, with the observed frequency of peak amplitude being consistent with those observed experimentally by others.","PeriodicalId":196124,"journal":{"name":"Proceeding of Ninth International Symposium on Turbulence and Shear Flow Phenomena","volume":"47 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":"133514468","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 FAST AND DIRECT METHOD FOR CHARACTERIZING HYDRAULIC ROUGHNESS","authors":"D. Chung, M. MacDonald, L. Chan, N. Hutchins, A. Ooi","doi":"10.1615/tsfp9.230","DOIUrl":"https://doi.org/10.1615/tsfp9.230","url":null,"abstract":"We describe a fast direct numerical simulation (DNS) method that promises to directly characterize the hydraulic resistance of any given rough surface, from the hydraulically smooth to the fully rough regime. The method circumvents the unfavorable computational cost associated with simulating high-Reynolds-number flows by employing minimal-span channels (Jiménez & Moin, 1991). Proofof-concept simulations, employing the parametric-forcing roughness model (Busse & Sandham, 2012), demonstrate that flows simulated in minimal-span channels are sufficient for capturing the downward velocity shift predicted by flows in full-span channels. Owing to the minimal cost, we are able to conduct parametric DNSs with increasing roughness Reynolds numbers while maintaining a fixed roughness height that is 40 times smaller than the half-channel height. When coupled to an unstructured-grid code, the present method promises a practical, fast and accurate tool for characterizing hydraulic resistance directly from profilometry data of rough surfaces.","PeriodicalId":196124,"journal":{"name":"Proceeding of Ninth International Symposium on Turbulence and Shear Flow Phenomena","volume":"53 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":"115680751","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":"EXPERIMENTS ON TURBULENCE MODULATION BY SURFACTANT ADDITIVES IN A PRECESSING SPHERE","authors":"S. Goto, Yasufumi Horimoto, G. Kawahara","doi":"10.1615/tsfp9.820","DOIUrl":"https://doi.org/10.1615/tsfp9.820","url":null,"abstract":"","PeriodicalId":196124,"journal":{"name":"Proceeding of Ninth International Symposium on Turbulence and Shear Flow Phenomena","volume":"1 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":"123843720","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":"Direct Numerical Simulation of Rapidly Distorting Compressible Homogeneous Turbulent Flow","authors":"Shuang Tan, Qibing Li, S. Fu","doi":"10.1615/tsfp9.570","DOIUrl":"https://doi.org/10.1615/tsfp9.570","url":null,"abstract":"","PeriodicalId":196124,"journal":{"name":"Proceeding of Ninth International Symposium on Turbulence and Shear Flow Phenomena","volume":"35 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":"124657231","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":"DYNAMICS OF PRIMARY AND SECONDARY VORTICES IN A SLOT JET","authors":"M. Shestakov, V. Dulin, M. Tokarev, D. Markovich","doi":"10.1615/tsfp9.700","DOIUrl":"https://doi.org/10.1615/tsfp9.700","url":null,"abstract":"","PeriodicalId":196124,"journal":{"name":"Proceeding of Ninth International Symposium on Turbulence and Shear Flow Phenomena","volume":"378 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":"116000034","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}