Abstract
With the aid of numerical method, both flow field and its accompanied loss mechanism within the rotating cavity are investigated in detail in the 1st part of the two parts paper. For ease of comparison, rotating cavity is further classified as the rotor-stator cavity case and the rotor-rotor cavity case. Results indicate that flow within both kinds of the cavity act as the inviscid flow except that the flow near walls, neighboring the lower G region and in the vicinity of the rotating orifices. In the regions except such inviscid-flow-dominate domains, the theoretical core rotation factor can be safely used to predict the swirl ratio within the cavity. When detailed flow pattern is considered, Ekman-type flow exists near periphery of the surface’s boundary layer where viscous effect is non-negligible. However, due to the complex profile of the simulated cavity case, vortices structure is varied within the cavity. By comparison, swirl ratio can be used to predict the magnitude of loss. Due to the relatively evident rotating effects of the rotor-rotor cavity, swirl ratio even increases to 1.4 in the current model, which means that flow is moving faster than the surrounding disc. Further investigation finds that this kind of highly rotating flow is accompanied with serious undesirable pressure loss. Parenthetically, unlike its counterpart, swirl ratio above 1.0 doesn’t happen when fluid passes through the rotor-stator cavity. So it is suggested that rotor-rotor flow cavity with the superimposed inward throughflow should be avoided in the engine design or certain measurements should be provided when such structure design is unavoidable. Simulation done in the current paper is meaningful since these dimensional parameters are typical in the design of state-of-art. Relatively lower range of Re φ and C w is not considered in the current two parts paper.
Similar content being viewed by others
References
Ekman V. W., On the Influence of the Earth's Rotation on Ocean-Currents[J]. Arkiv Mater N. astr. fysik Bd, 1905.
Daily J. W., Nece R. E., Chamber Dimension Effects on Induced Flow and Frictional Resistance of Enclosed Rotating Disks[J]. Journal of Basic Engineering, 1960, 82(1): 217–224.
Owen J. M., Roger R. H., Flow and Heat Transfer in Rotating-Disc Systems. Volume I -Rotor-Stator Systems. John Wiley and Sons Inc, New York, NY (USA) 1989.
Poncet S., Chauve M. P., Schiestel R., Batchelor Versus Stewartson Flow Structures in a Rotor-Stator Cavity with Throughflow[J]. Physics of Fluids, 2005, 17(7): 253–668.
Hart K. J., Turner A. B., Influence of Radial Inflow on Rotor-Stator Cavity Pressure Distributions[C]. ASME International Gas Turbine & Aeroengine Congress & Exposition, Cologne, Germany, 1994, 94-GT-106.
Hart K. J., Turner A. B., Simple Design Methods for the Prediction of Radial Static Pressure Distributions in a Rotor-Stator Cavity With Radial Inflow[C]. ASME International Gas Turbine and Aeroengine Congress and Exposition, Houston, Texas, USA, 1995, 95-GT-212.
Laroche E., Desportes S., Djaoui M., et al. A Combined Experimental and Numerical Investigation of the Flow in a Heated Rotor/Stator Cavity, with Radial Inflow[C]. ASME International Gas Turbine and Aeroengine Congress and Exhibition, Indianapolis, Indiana, USA, 1999, 99-GT-170.
Moghaddam E. R., Coren D., Long C., et al. A Numerical Investigation of Moment Coefficient and Flow Structure in a Rotor-Stator Cavity With Rotor Mounted Bolts[J]. Journal of Power & Energy, 2011, 227(3): 306–327.
Brillert D., Lieser D., Reichert A. W., et al. Total Pressure Losses in Rotor Systems With Radial Inflow[C]. ASME Turbo Expo: Power for Land, Sea, and Air, Munich, Germany. 2000, 2000-GT-0283.
Chew J. W., Farthing P. R., Owen J. M., Stratford B. B., The Use of Fins to Reduce the Pressure Drop in a Rotating Cavity With a Radial Inflow[J]. Journal of Turbomachinery, 1989, 111(3): 349–356.
LIU Guang, DU Qiang, LIU Jun, WANG Pei, ZHU. J. Q., Numerical Investigation of Radial Inflow in the Impeller Rear Cavity with and Without Baffle [J]. Science China Technological Sciences, 2016, 59(3): 1–12.
Hüning M., Comparison of Discharge Coefficient Measurements and Correlations for Several Orifice Designs With Cross-Flow and Rotation Around Several Axes[C]. ASME International Gas Turbine and Aeroengine Congress and Exhibition, Berlin, Germany, 2008, 08-GT-50976.
May D., Chew J. W., Scanlon T. J., Prediction of De-Swirled Radial Inflow in Rotating Cavities With Hysteresis[J]. Journal of Turbomachinery, 2013, 135(4): 928–935.
Acknowledgement
The authors want to thank the National Natural Science Foundation of China for sponsoring the research described in the current paper (No.51406204).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Gao, J., Du, Q., Liu, J. et al. Flow development through HP & LP turbines, Part I: Inward rotating cavity flow with superimposed throughflow. J. Therm. Sci. 26, 297–307 (2017). https://doi.org/10.1007/s11630-017-0942-7
Received:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s11630-017-0942-7