Download or read book Investigation of the 3D Unsteady Rotor Pressure Field in an HP Turbine Stage written by E. Valentini and published by . This book was released on 2002 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of the Unsteady Rotor Boundary Layer Transition in a Transonic High Pressure Turbine Stage written by Maik Tiedemann and published by . This book was released on 1998 with total page 132 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Investigation of the Unsteady Rotor Boundary Layer Transition in a Transonic High Pressure Turbine Stage written by Maik Tiedemann and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings of the National Aerospace Propulsion Conference written by Chetan S. Mistry and published by Springer Nature. This book was released on 2020-07-31 with total page 534 pages. Available in PDF, EPUB and Kindle. Book excerpt: This volume presents selected papers presented during the National Aerospace Propulsion Conference (NAPC) held at Indian Institute of Technology Kharagpur. It brings together contributions from the entire propulsion community, spanning air-breathing and non-air-breathing propulsion. The papers cover aerospace propulsion-related topics, and discuss relevant research advances made in this field. It will be of interest to researchers in industry and academia working on gas turbine, rocket, and jet engines.

Download or read book Investigation of the Unsteady Rotor Boundary Layer Transition in a Transonic High Pressure Turbine Stage written by Maik Tiedemann and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 3 D Unsteady Simulation of a Modern High Pressure Turbine Stage written by Vikram Shyam and published by . This book was released on 2010 with total page 121 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: This is the first 3-D unsteady RANS simulation of a highly loaded transonic turbine stage and results are compared to steady calculations and experiments. A low Reynolds number [kappa]-[epsilon] turbulence model is employed to provide closure for the RANS system. Phase-lag is used in the tangential direction to account for stator-rotor interaction. Due to the highly loaded characteristics of the stage, inviscid effects dominate the flowfield downstream of the rotor leading edge minimizing the effect of segregation to the leading edge region of the rotor blade. Unsteadiness was observed at the tip surface that results in intermittent 'hot spots'. It is demonstrated that unsteadiness in the tip gap is governed by both inviscid and viscous effects due to shock-boundary layer interaction and is not heavily dependent on pressure ratio across the tip gap. This is contrary to published observations that have primarily dealt with subsonic tip flows. The high relative Mach numbers in the tip gap lead to a choking of the leakage flow that translates to a relative attenuation of losses at higher loading. The efficacy of a new tip geometry is discussed to minimize heat flux at the tip while maintaining choked conditions. Simulated heat flux and pressure on the blade and hub agree favorably with experiment and literature. The time-averaged simulation provides a more conservative estimate of heat flux than the steady simulation. The shock structure formed due to stator-rotor interaction is analyzed. A preprocessor has also been developed as a conduit between the unstructured multi-block grid generation software GridPro and the CFD code TURBO.

Download or read book Investigation of the Unsteady Rotor Aerodynamics in a Transonic Turbine Stage written by Von Karman Institute for Fluid Dynamics and published by . This book was released on 2000 with total page 12 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Proceedings of the ASME Turbo Expo written by and published by . This book was released on 2005 with total page 826 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Engineering Fluid Dynamics 2018 written by Bjørn H. Hjertager and published by MDPI. This book was released on 2020-01-15 with total page 256 pages. Available in PDF, EPUB and Kindle. Book excerpt: “Engineering Fluid Dynamics 2018”. The topic of engineering fluid dynamics includes both experimental as well as computational studies. Of special interest were submissions from the fields of mechanical, chemical, marine, safety, and energy engineering. We welcomed both original research articles as well as review articles. After one year, 28 papers were submitted and 14 were accepted for publication. The average processing time was 37.91 days. The authors had the following geographical distribution: China (9); Korea (3); Spain (1); and India (1). Papers covered a wide range of topics, including analysis of fans, turbines, fires in tunnels, vortex generators, deep sea mining, as well as pumps.

Download or read book Design and Experimental Investigation of a High weight flow Low pressure ratio Turbine written by and published by . This book was released on 1959 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Effects of Aerodynamic Unsteadiness in Axial Turbomachines written by R. Dénos and published by . This book was released on 2005 with total page 632 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Design and Experimental Investigation of Two Rotor Blade Modifications for a High weight flow Low pressure ratio Turbine written by Robert R. Nunamaker and published by . This book was released on 1959 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Experimental Investigation of Partial and Full admission Characteristics of a Two stage Velocity compounded Turbine written by Thomas P. Moffitt and published by . This book was released on 1960 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Time Accurate Prediction of the Viscous Flow in a Turbine Stage Including a Rotor in Motion written by Akamol Shavalikul and published by . This book was released on 2009 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract A time accurate prediction of the viscous flow in a turbine stage including a rotor in motion By Akamol Shavalikul The actual flow field in a turbine stage is extremely complex, three-dimensional, and unsteady, mainly due to interactions between the nozzle guide vanes (NGV) and the rotor vanes. A detailed understanding of turbine flow field characteristics, which is crucial for improving turbine performance, can be obtained using a computational fluid dynamics approach. In this current study, the flow field in the Pennsylvania State University Axial Flow Turbine Research Facility (AFTRF) was simulated using a three-dimensional Reynolds Averaged Navier-Stokes finite volume solver (RANS). This study examined four sets of simulations. The first set of flow simulations is an individual NGV passage flow field without the influence of a rotor blade row. The simulation results were used to produce the flow visualization in an NGV passage, which provide more detailed NGV flow characteristics. Secondly, a set of a rotor flow simulations was carried out to examine the flow fields associated with different pressure side tip extension configurations, which are designed to reduce the tip leakage flow. RANS based viscous flow simulations were used to compare a number of potential aerodynamic de-sensitization designs for blade tips. The last two sets use a multiple reference frames approach for a complete turbine stage with two different interface models. The first interface model is the circumferentially averaged mixing plane model. The quasi-steady state flow characteristics of the AFTRF can be obtained from this interface model. This model was not only used to investigate the flow characteristics in the turbine stage but also the effects of using pressure side rotor tip extensions. The tip leakage flow fields simulated from this model and from the linear cascade model show similar trends. More detailed understanding of unsteady characteristics of a turbine flow field can be obtained using the second type of interface model, the time accurate sliding-mesh model. The potential flow interactions, wake characteristics, their effects on secondary flow formation, and the wake mixing process in a rotor passage were examined using this model. A comparison between the results from the circumferential average model and the time accurate flow model results is presented. It was found that the circumferential average model cannot accurately simulate flow interaction characteristics on the interface plane between the NGV trailing edge and the rotor leading edge. However, the circumferential average model does give accurate flow characteristics in the NGV domain and the rotor domain with less computational time and computer memory requirements. In contrast, the time accurate flow simulation can predict all unsteady flow characteristics occurring in the turbine stage, but with high computational resource requirements.

Download or read book Vane rotor Unsteady Aerodynamics of a Single Stage High Pressure Turbine written by Ryan M. Urbassik and published by . This book was released on 2003 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Unsteady Aerodynamics of High Work Turbines written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: One method aircraft engine manufactures use to minimize engine cost and weight is to reduce the number of parts. A significant reduction includes reducing the turbine blade count or combining two moderately loaded turbines into one high-work turbine. The risk of High Cycle Fatigue in these configurations is increased by the additional aerodynamic forcing generated by the high blade loading and the nozzle trailing edge shocks. A lot of research has been done into the efficiency implications of supersonic shocks in these configurations. However what is less well understood is the resulting unsteady rotor forces. These unsteady aerodynamics aspects are the focus of this research. The research investigates where manufacturers might concentrate their resources to reduce Direct Operating Costs (DOC). It compares the relative financial implications of disruption events to the cost of reducing DOC by further efficiency gains. The technical aspects of the research use computational aerodynamic modelling of a high work turbine to explore the unsteady aerodynamics and the resulting rotor forces. Investigation of parametric models into the effect of reaction, axial spacing, pressure ratio, the nozzle wake profile and the significance of the rotor boundary layer in dissipating the high gradient shocks is also investigated. Data from an experimental test program was used to characterise sub- and super-critical shock boundary layer interactions to determine if they are a significant forcing function. The primary conclusions from this research include the relative merits of targeting resources into reducing disruption events rather than the relatively small financial gains which might be gained through further efficiency improvement by researching advanced technologies. The computational method is validated against an experimental dataset from a high-speed turbine stage rig. Overall, good agreement is found between the measurements and the predictions for both the detailed unsteady.

Download or read book Comparison of Steady and Time accurate Predictions with Experiment for the Aerodynamics of a Fully Cooled Single stage High pressure Turbine written by Suzanne A. Southworth and published by . This book was released on 2006 with total page 200 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: The aerodynamics of a fully cooled single stage high-pressure turbine operating at design corrected conditions has been the subject of a thorough study involving experimental and computational work. The experimental configuration included a fully cooled, full-stage high-pressure turbine stage operating at design corrected conditions of corrected speed, flow function, and stage pressure ratio. The data reported in this thesis were obtained for a relatively low vane inlet Reynolds number condition in order to test the limits of the experimental system. The vanes and blades of the turbine and the stationary shroud immediately above the blade were instrumented. The vanes were instrumented with heat-flux gauges and pressure transducers at one span wise external location and two internal locations. The blades were instrumented with heat-flux gauges and pressure transducers at three different span wise external locations to provide external heat-flux and surface-pressure distributions, and internally with pressure transducers and miniature thermocouples to provide pressure and temperature histories within the airfoil cooling cavities. The stationary shroud was instrumented with heat-flux gauges and pressure transducers at several axial chord locations. Kulite pressure transducers were used to obtain all of the pressure data and double-sided Kapton heatflux gages were used for the heat transfer measurements on the vanes and blades while button-type gauges were used in the stationary shroud. Aerodynamic predictions were obtained using the computational fluid dynamics (CFD) codes Numeca's FINE/Turbo and Mississippi State University (MSU) Turbo, but for both calculations the addition of the film cooling gas was ignored. Further calculations are in progress that do include the film cooling, but results from those calculations are not reported herein. Both of these codes are 3D viscous codes, but FINE/Turbo was used to obtain both steady and time-accurate results while MSUTURBO was used to obtain only time-accurate results. Both FINE/Turbo and MSU Turbo utilize phase lagged boundary conditions to simplify the model and significantly reduce computing time and resources. The unsteady loadings, as predicted and measured, are compared for the blade, vane, and shroud as time-averaged, time series, and power series data. The steady CFD prediction was also obtained so as to provide the initial boundary conditions for the unsteady prediction. Therefore, comparisons of the steady CFD predictions and the time- averaged data were also made. The blade included a recessed tip geometry, which was included in the CFD model, and the CFD analysis also investigated different tip/shroud clearances to investigate the influence of the tip cap height on the downstream flow field. The analysis shows that both the steady state and time-accurate pressure predictions compare quite well with the experimental results. The steady and timeaveraged vane predictions are closer to the data than the steady prediction for the blade, but that is to be expected with the unsteady nature of the flow over the blade. The timeaccurate prediction for the blade is in very good agreement with the experimental results. The FINE/Turbo heat transfer predictions (MSU Turbo doesn't do heat-transfer predictions at the present time) are not showing similar trends as the data but this is likely due to the fact that the film cooling was ignored and due to the grid density utilized for these calculations. Since this work is meant to be a true prediction without any model optimization, it is interesting to see where the CFD produces the best results and where it has the most difficulty. It is also important to keep in mind that this work compares an uncooled CFD prediction to data obtained for a fully cooled turbine stage. This is the first time such data has been available and the uncooled CFD predictions will lend insight into the importance of cooling modeling, which has yet to become developed to a point that it is widely used in CFD predictions. Overall, the comparisons made here demonstrate the ability of two different CFD codes to successfully capture the unsteady flow physics on the blade surface and in the blade tip/stationary shroud region.