3 edition of A reduced model for prediction of thermal and rotational effects on turbine tip clearance found in the catalog.
A reduced model for prediction of thermal and rotational effects on turbine tip clearance
Javier A. Kypuros
by National Aeronautics and Space Administration, Glenn Research Center in [Cleveland, Ohio]
Written in English
|Statement||Javier A. Kypuros, Kevin J. Melcher.|
|Series||[NASA technical memorandum] -- NASA/TM-2003-212226., NASA technical memorandum -- 212226.|
|Contributions||Melcher, Kevin J., NASA Glenn Research Center.|
|The Physical Object|
Full text of "Fatigue life prediction modeling for turbine hot section materials" See other formats NASA Technical Memorandum Fatigue Life Prediction Modeling for Turbine Hot Section Materials (KiSA-TM) FATIGUE LIFE PEEDIC!EION N EiODELlNG FOR TOBBINE HOT SECTION MATSBiaiS iWkSk) 17 p CSCiu 2aK * UBclas G3/39 OliaiOi* G.R. . A commercial CFD code, namely, Fluent V with a k-ɛ two-equation turbulence model was utilized in order to study the effects of tip clearance on the overall performance of each fan with the tip clearances ranging from 5 to 30 mm. The numerical results were compared with the experimental data reported previously in the literature by the Cited by:
DeCastro, J.A.; and Melcher, K.J.: “A Study on the Requirements for Fast Active Turbine Tip Clearance Control Systems,” NASA TM, also AIAA, Presented at the 40th AIAA/ASME/SAE/ASEE Joint Propulsion Conference & Exhibit, July , complex nature of tip clearance flows. An annular turbine cascade with a rotating outer casing was used to simulate the relative motion at the tip of an axial rotor. It was found that relative motion did not have a significant effect on the basic structure of the micro-flow, even though it reduced.
closure models, and so called Low-Reynolds (low-Re) number and two-layer turbulence models. However, in many cases CFD heat transfer predictions based on these standard models still show a largedegreeofuncertainty, which canbeattributedtotheuseofthe-equation as the turbulence scale equation and the associated limitations of the near wall by: – Thermal – Combustion – Structural mechanics • Tip clearance • Volute Geometry – Understand the effect of grid size on prediction • Target: “working grid” size with Y+=2 • Ideally, double/half the grid size in each direction – 1/8X, 1X, 8X working grid size.
A Reduced Model for the Prediction of Thermal and Rotational Effects on Turbine Tip Clearance Javier A. Kypuros Abstract This paper describes a dynamic model that was developed to predict changes in turbine tip clearance – the radial distance between the end of a turbine blade and the abradable tip seal.
The clearance. Get this from a library. A reduced model for prediction of thermal and rotational effects on turbine tip clearance.
[Javier A Kypuros; Kevin J Melcher; NASA Glenn Research Center.]. A reduced model for prediction of thermal and rotational effects on turbine tip clearance. The clearance is estimated by using a first principles approach to model the thermal and mechanical effects of engine operating conditions on the turbine sub-components.
These effects are summed to determine the resulting clearance. The model is demonstrated via a ground idle to maximum power transient and a lapse-rate takeoff transient. Results show the model Author: Javier A. Kypuros and Kevin J. Melcher. “A Reduced Model for Prediction of Thermal and Rotational Effects on Turbine Tip Clearance,” NASA Technical Memorandum, NASA TM • Steinetz, B.
M., Taylor S., Oswald, J., DeCastro, J. A., “Seal Investigations of an Active Clearance Control System Concept,” 11th International Symposium on. Kypuros J A and Melcher K J A Reduced Model for Prediction of Thermal and Rotational Effects on Turbine Tip Clearance NASA/TM Google Scholar.
Wilde J and Lai Y Design optimization of an eddy current Cited by: 8. The primary tip leakage vortex (PTLV) trajectory is specially studied with consideration of the tip clearance size δ, the impeller blade number Z i, and the impeller rotational speed n.
The results show that δ slightly shifts the separation point (SP) of the PTLV but rarely affects the separation angle by: 1. Kypuros, and K. Melcher, “A reduced model for prediction of thermal and rotational effects on turbine tip clearance,” NASN/TM—, March Cited by: 1.
Design,Simulation and Performance on the Effect of Modification on Impeller Tip for Pump as Turbine (PAT) Nan Kathy Lin*, publications in recent years emphasize the importance of using simple turbine in order to reduce the cost of produced electrical theoretical frameworks and prediction models, the best approach is to test the pump.
models for this elementary sound source found in the literature vary substantially. Combining selected sub-models, a preliminary own wind turbine sound prediction model was compiled and encoded, yielding the acoustic footprint of the turbine on ground level and the swishing character of the wind turbine sound.
Wind Turbine Blade Design Peter J. Schubel * and Richard J. Crossley The discontinued mainstream development of the VAWT can be attributed to a low tip speed ratio and difficulty in controlling rotor speed. Difficulties in the starting of vertical turbines Avoiding low tip speed ratios which increase wake rotationCited by: J.
Kypuros and K. Melcher, “A reduced model for prediction of thermal and rotational effects on turbine tip clearance,” Tech. Rep. NASA/ TM, View at: Cited by: 4. Effects of Endwall Motion on the Aero-Thermal Performance of a Winglet Tip in a HP Turbine 17 September | Journal of Turbomachinery, Vol.No.
6 Reduction of Tip Clearance Losses in an Unshrouded Turbine by Rotor Casing Contouring. effect on turbine blade tip heat transfer. The first-of-its-kind experimental data from transient thermal measurements obtained in a low-speed high-temperature linear cascade are reported for a range of tip clearances (%, %, % and 1%).
Comparisons are made for. Kypuros, J.A., Melcher, K.J.: A reduced model for prediction of thermal and rotational effects on turbine tip clearance.
NASA/TM–– () Google ScholarCited by: The benefits of reducing the tip clearance have been receiving many scholars’ attention all the time, which bring turbine efficiency increasing, emissions reduction, payloads increasing, and mission range abilities extension.
In order to gain the blade tip clearance dynamically, a prototype optical fiber measurement system was built and tested based on the rotor test by: 4. Effect of Tip-Speed Constraints on the Optimized Design of a Wind Turbine a low tip-speed ratio/high-solidity rotor design, a high tip-speed ratio/low-solidity rotor design, and a ﬂexible blade design in which a high tip-speed Overall turbine costs were reduced only 3% from the optimized m/s case.
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The clearance is estimated by using a first principles approach to model the thermal and mechanical effects of engine operating conditions on the turbine sub-components. These effects. Fast Calculation Methods for the Modelling of Transient Temperature Fields in a Steam Turbine in Pre-warming Operation at low volume flow and high rotational speed and causes a To model the thermal boundary, the Low Reynolds kω-SST turbulence model is Size: KB.
Thus an HCO rotor shift towards the gas turbine inlet decreases the blade tip clearance in the turbine but increases those in the compressor. However, since turbine power is twice the power to drive the compressor and the conical turbine case is four times steeper than that of the compressor, compressor tip losses are only one-eighth of the Author: Lee S.
Langston.Turbine efficiency is the ratio of actual work output of the turbine to the net input energy supplied in the form of fuel.
For stand-alone gas turbines, without any heat recovery system the efficiency will be as low as 35 to 40 per cent. This is attributed to the blade efficiency of the rotor, leakage through clearance spaces, friction.
Sealing in Turbomachinery. Effect of thermal–physical properties on the abradability of seal coating under high-speed rubbing condition. The effects of clearance sizes on labyrinth brush seal leakage performance using a Reynolds-averaged Navier—Stokes solver and non-Darcian porous medium by: