International Journal of Turbomachinery, Propulsion and Power最新文献_第5页

Impact of Unsteady Wakes on the Secondary Flows of a High-Speed Low-Pressure Turbine Cascade 非定常尾迹对高速低压涡轮叶栅二次流动的影响

International Journal of Turbomachinery, Propulsion and Power Pub Date : 2023-09-22 DOI: 10.3390/ijtpp8040036

Gustavo Lopes, Loris Simonassi, Sergio Lavagnoli

引用次数: 1

Characterization of Unsteady Leakage Flow in an Axial Fan 轴流风机非定常泄漏流特性研究

International Journal of Turbomachinery, Propulsion and Power Pub Date : 2023-09-13 DOI: 10.3390/ijtpp8030034

Matteo Dellacasagrande, Edward Canepa, Andrea Cattanei, Mehrdad Moradi

{"title":"Characterization of Unsteady Leakage Flow in an Axial Fan","authors":"Matteo Dellacasagrande, Edward Canepa, Andrea Cattanei, Mehrdad Moradi","doi":"10.3390/ijtpp8030034","DOIUrl":"https://doi.org/10.3390/ijtpp8030034","url":null,"abstract":"The present work reports an experimental study of the leakage flow in a low-speed fan ring. Existing 2D Particle Image Velocimetry (PIV) measurements taken in a meridional plane in front of the rotor gap have been further processed and analyzed by means of the Proper Orthogonal Decomposition (POD). Three values of the dimensionless pressure rise across the rotor have been investigated. Namely, attention has been focused on the intermediate case—the one for which a strong radial oscillation in the leakage flow has been observed: POD results have shown that, in this condition, the leakage flow exhibits periodic radial oscillations that are not correlated to the periodic blade passing. Moreover, such coherent motions have been found to promote turbulence transport at different radial positions, whereas rotor-related oscillations have a negligible effect in this sense. The present POD procedure can be generally applied to turbomachinery flows to characterize their unsteady behavior beside the classical phase-averaging methods based on rotor-related quantities. The present approach is novel for the study of leakage flow dynamics in axial fans.","PeriodicalId":36626,"journal":{"name":"International Journal of Turbomachinery, Propulsion and Power","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"135781632","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: 0

Effects of Periodic Incoming Wakes on the Aerodynamics of a High-Speed Low-Pressure Turbine Cascade 周期性来流尾迹对高速低压涡轮叶栅气动特性的影响

International Journal of Turbomachinery, Propulsion and Power Pub Date : 2023-09-13 DOI: 10.3390/ijtpp8030035

Loris Simonassi, Gustavo Lopes, Sergio Lavagnoli

{"title":"Effects of Periodic Incoming Wakes on the Aerodynamics of a High-Speed Low-Pressure Turbine Cascade","authors":"Loris Simonassi, Gustavo Lopes, Sergio Lavagnoli","doi":"10.3390/ijtpp8030035","DOIUrl":"https://doi.org/10.3390/ijtpp8030035","url":null,"abstract":"The influence of unsteady wakes incoming from the upstream stages is of high relevance in modern high-speed, low-pressure turbines (LPT) operating at transonic exit Mach numbers and low Reynolds numbers for their potential to trigger transition and influence the separation of the boundary layer on the blade suction side. The aim of this paper is the experimental characterization of the influence of incoming wakes on the 2D aerodynamics of a high-speed LPT cascade operating at a low Reynolds number and transonic exit Mach number. A detailed analysis of the status of the flow along the blade under investigation and its impact on the profile loss are presented for a range of Mach numbers from 0.70 to 0.95 and Reynolds numbers from 70k to 120k under steady and unsteady inflow conditions. Tests were conducted at on- and off-design engine realistic conditions in the VKI S-1/C wind tunnel on the SPLEEN C1 transonic cascade. The wakes incoming from an upstream blade row have been replicated using a set of rotating bars, which shed wakes at an engine-representative reduced frequency (f+=0.95) and flow coefficient (Φ=0.80). A set of densely instrumented traversable blades were used to sample the surface pressure distributions. The development of the boundary layers along the blade suction side is examined through quasi-wall shear stress obtained with surface-mounted hot-film sensors. Wake traverses were carried out downstream of the cascade with a miniaturized L-shaped five-hole probe to characterize the blade losses. The introduction of periodic incoming wakes promotes variations in the flow topology over the blade. The effect on the suction side separation bubble is shown to depend on the exit flow conditions. At low Mach numbers, the incoming wakes determine a reduction in the size of the bubble; in contrast, this effect is not registered as the exit Mach number increases. Consistently, a high dependence of the unsteady wake effect on the profile loss on the exit Reynolds and Mach numbers is demonstrated.","PeriodicalId":36626,"journal":{"name":"International Journal of Turbomachinery, Propulsion and Power","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2023-09-13","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134990241","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: 1

Acoustic Boundary Conditions for Can-Annular Combustors 罐式环形燃烧器的声学边界条件

IF 1.4

International Journal of Turbomachinery, Propulsion and Power Pub Date : 2023-09-08 DOI: 10.3390/ijtpp8030032

James Brind

引用次数: 0

Potential of Static Pressure Recovery of Rotor-Only Low-Pressure Axial Fans 纯转子低压轴流风机静压恢复潜力

IF 1.4

International Journal of Turbomachinery, Propulsion and Power Pub Date : 2023-09-08 DOI: 10.3390/ijtpp8030033

Hauke Witte, C. Bode, Jens Friedrichs

引用次数: 0

Experimental Validation of a Numerical Coupling Environment Applying FEM and CFD 应用有限元和CFD的数值耦合环境的实验验证

IF 1.4

International Journal of Turbomachinery, Propulsion and Power Pub Date : 2023-09-04 DOI: 10.3390/ijtpp8030031

Christopher Hartmann, Julia Schweikert, F. Cottier, Ute Israel, Jochen Gier, Jens von Wolfersdorf

{"title":"Experimental Validation of a Numerical Coupling Environment Applying FEM and CFD","authors":"Christopher Hartmann, Julia Schweikert, F. Cottier, Ute Israel, Jochen Gier, Jens von Wolfersdorf","doi":"10.3390/ijtpp8030031","DOIUrl":"https://doi.org/10.3390/ijtpp8030031","url":null,"abstract":"Experimental results for the transient heat transfer characteristics over a flat plate and over a plate with V-shaped ribs were compared to numerical results from a coupling environment applying FEM and CFD. In order to simulate transient effects in the cooling process of engine components during typical flight missions, the temperature and the velocity at the inlet of the channel were varied over time. The transient temperature distribution at the plate was measured using infrared thermography. Five different plate materials (perspex, PEEK, quartz, aluminum, and steel) were considered to investigate the influence of thermal conduction on the heat transfer between solid and fluid depending on the Biot number. The experimental results represent a reference database for a Python-based coupling environment applying CalculiX (FEM) and ANSYS CFX (CFD). The results were additionally compared to numerical results simulating the complete transient conjugated heat transfer with CFD. A good agreement between the numerical and the experimental results was achieved using different coupling sizes at different Biot numbers for the flat plate and the plate with V-shaped ribs.","PeriodicalId":36626,"journal":{"name":"International Journal of Turbomachinery, Propulsion and Power","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-09-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49523575","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: 0

Effect of Tip Gap Size on the Performance of an Axial Compressor Stage with and without Active Flow Control 叶尖间隙尺寸对有无主动流量控制的轴流压气机级性能的影响

IF 1.4

International Journal of Turbomachinery, Propulsion and Power Pub Date : 2023-09-01 DOI: 10.3390/ijtpp8030030

Clémence Rannou, Julien Marty, Geoffrey Tanguy, A. Dazin

引用次数: 0

Suitability of a Profile with Tubercles for Axial Pumps—Investigation Using Flow Simulation 带圆管型面适用于轴流泵——流动模拟研究

IF 1.4

International Journal of Turbomachinery, Propulsion and Power Pub Date : 2023-09-01 DOI: 10.3390/ijtpp8030029

Mareen Derda, Ferdinand Neumann, P. Thamsen

{"title":"Suitability of a Profile with Tubercles for Axial Pumps—Investigation Using Flow Simulation","authors":"Mareen Derda, Ferdinand Neumann, P. Thamsen","doi":"10.3390/ijtpp8030029","DOIUrl":"https://doi.org/10.3390/ijtpp8030029","url":null,"abstract":"Even if wind tunnel tests and simulations have confirmed that tubercles can influence the behaviour of a profile, research in the field of axial pumps has so far been lacking. However, previous studies cannot be transferred to the application of axial pumps, since the requirements for the profile geometry as well as the Reynolds number range differ. The present study aims to address this research gap by performing a CFD simulation with a profile common for axial pumps, the Goe11K, testing four different tubercle configurations. At the same time, this simulation is a preliminary study for experimental tests. The results show that certain tubercle configurations improve the behaviour of the profile in the post-stall area, i.e., increase the lift of the profile at large angles of attack (α). In general, the curve of the profiles with tubercles runs more evenly, without the drastic drop in lift. This improved property comes at the expense of lower maximum lift and increased drag at lower α. With regard to the use of axial pumps, it can be concluded that there are advantages, particularly in the partial load range. These could ultimately enlarge the operation range of an axial pump.","PeriodicalId":36626,"journal":{"name":"International Journal of Turbomachinery, Propulsion and Power","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"49540510","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: 0

Three-Dimensional Flow Simulation by a Hybrid Two-Phase Solver for the Assessment of Liquid/Gas Transport in a Volute-Type Centrifugal Pump with Twisted Blades 涡旋叶片蜗壳式离心泵液/气输运三维流动模拟研究

IF 1.4

International Journal of Turbomachinery, Propulsion and Power Pub Date : 2023-08-30 DOI: 10.3390/ijtpp8030028

Markus Hundshagen, Kevin Rave, M. Mansour, D. Thévenin, R. Skoda

{"title":"Three-Dimensional Flow Simulation by a Hybrid Two-Phase Solver for the Assessment of Liquid/Gas Transport in a Volute-Type Centrifugal Pump with Twisted Blades","authors":"Markus Hundshagen, Kevin Rave, M. Mansour, D. Thévenin, R. Skoda","doi":"10.3390/ijtpp8030028","DOIUrl":"https://doi.org/10.3390/ijtpp8030028","url":null,"abstract":"A hybrid two-phase flow solver is proposed, based on an Euler–Euler two-fluid model with continuous blending of a Volume-of-Fluid method when phase interfaces of coherent gas pockets are to be resolved. In a preceding study on a two-dimensional bladed research pump with reduced rotational speed, the transition from bubbly flow to coherent steady gas pockets observed in optical experiments with liquid/gas flow could be well captured by the hybrid solver. In the present study, the experiments and solver validation are extended to an industrial-scale centrifugal pump with twisted three-dimensional blades and elevated design rotational speed. The solver is combined with a population balance model, and a scale-adaptive turbulence model is employed. Compared to the two-dimensional bladed pump, the transition from agglomerated bubbles flow to attached gas pockets is shifted to larger gas loading, which is well captured by the simulation. The pump head drop with increasing gas load is also reproduced, showing the hybrid solver’s validity for realistic pump operation conditions.","PeriodicalId":36626,"journal":{"name":"International Journal of Turbomachinery, Propulsion and Power","volume":null,"pages":null},"PeriodicalIF":1.4,"publicationDate":"2023-08-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"42353119","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: 0

Effect of the von Karman Shedding Frequency on the Hydrodynamics of a Francis Turbine Operating at Nominal Load von Karman脱落频率对额定负荷下混流式水轮机水动力特性的影响

IF 1.4

International Journal of Turbomachinery, Propulsion and Power Pub Date : 2023-08-07 DOI: 10.3390/ijtpp8030027

Giacomo Zanetti, G. Cavazzini, A. Santolin

引用次数: 0