PRESSURE DISTRIBUTION ON THE BLADE SURFACE OF AN AUTOMOTIVE MIXED FLOW TURBOCHARGER TURBINE UNDER PULSATING FLOW CONDITIONS

Authors

  • M.H. Padzillah UTM Centre for Low Carbon Transport in cooperation with Imperial College London, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia,81310 UTM Johor Bahru, Malaysia
  • S. Rajoo UTM Centre for Low Carbon Transport in cooperation with Imperial College London, Faculty of Mechanical Engineering, Universiti Teknologi Malaysia,81310 UTM Johor Bahru, Malaysia
  • R.F. Martinez-Botas Department of Mechanical Engineering, Imperial College London, London SW7 2AZ, United Kingdom

DOI:

https://doi.org/10.11113/jt.v78.9596

Keywords:

Mixed-flow turbine, computational fluid dynamics, pulsating flow

Abstract

The increment of the contribution to CO2 release by transportation industry as other sectors are decarbonizing is evident. As number of world population continue to increase, the task of developing highly downsized high power-to-weight ratio engines are critical. Over more than a hundred years of invention, turbocharger remains a key technology that enable highly boosted efficient engine. Despite its actual operating environment which is pulsating flow, the turbocharger turbine that is available to date is still designed and assessed under the assumption of steady flow conditions. This is attributable to the lack of understanding on the insight of the flow field effect towards the torque generation of the turbine blade under pulsating flow conditions. This paper presents an effort towards investigating the influence of pulsating flow on the blade loading and its differences from steady state conditions through the use of Computational Fluid Dynamics (CFD). For this purpose, a lean-vaned mixed-flow turbine with rotational speed of 30000 rpm at 20 Hz flow frequency, which represent turbine operation for 3-cylinder 4-stroke engine operating at 800 rpm has been used. Results presented in terms of spanwise location of the blade indicated different behavior at each location. Close to the hub, there are strong flow separation that hinders torque generation is seen while at mid-span more torque is generated under unsteady flow as compared to its steady counterpart. Moreover, close to the shroud, the pressure difference between steady and pulsating flow is almost identical

References

A. Dale and N. Watson. 1986. Vaneless Radial Turbocharger Turbine Performance, Proc. IMechE Int. Conf. Turbocharging Turbochargers (Mechanical Eng. Publ. London). 65–76.

S. S. Shamsi. 1979. Estimating the Influence of Pulsating Flow Conditions on the Performance of a Turbine. SAE Technical Paper 790068

J. .-W. Lam, Q. D. H. Roberts, and G. T. McDonnel. 2002. Flow Modelling of a Turbocharger Turbine Under Pulsating Plow, Preceedings IMechE Int. Conf. Turbochargers Turbochargnig.181–197.

D. Palfreyman and R. F. Martinez-Botas. 2004. The Pulsating Flow Field in a Mixed Flow Turbocharger Turbine: An Experimental and Computational Study. Proceedings of the ASME Turbo Expo 2004. 5:697–708.

D. Palfreyman and R. Martinez-Botas, 2002, Numerical Study of the Internal Flow Field Characteristics in Mixed Flow Turbines, Proc ASME Turbo Expo No. GT2002-30372.

N. Karamanis, R. F. Martinez-Botas, and C. C. Su. 2001. Mixed Flow Turbines: Inlet and Exit Flow Under Steady and Pulsating Conditions. Journal of Turbomachines. 123(2): 359.

N. Karamanis, D. Palfreyman, C. Arcoumanis, and R. F. Martinez-Botas. 2006. Steady and Unsteady Velocity Measurements in a Small Turbocharger Turbine with Computational Validation. Journal of Physics Conference Series. 45(1):173.

M. H. Padzillah, S. Rajoo, and R. F. Martinez-Botas. 2015. Phase Shift Methodology Assessment of an Automotive Mixed Flow Turbocharger Turbine Under Pulsating Flow Conditions. Jurnal Teknologi. 77(8):29–35.

M. H. Padzillah, S. Rajoo, and R. F. Martinez-Botas, 2015, Experimental and Numerical Investigation on Flow Angle Characteristics of an Automotive Mixed Flow Turbocharger Turbine. Jurnal Teknologi. 77(8):7–12.

M. H. Padzillah, S. Rajoo, and R. F. Martinez-Botas. 2015. Flow Field Analysis of an Automotive Mixed Flow Turbocharger Turbine. Jurnal Teknologi. 77(8):21–27.

F. Hellstrom and L. Fuchs. 2008. Effects of Inlet Conditions on the Turbine Performance of a Radial Turbine. Volume 6: Turbomachinery, Parts A, B, and C. 6:1985–2001.

C. D. Copeland, R. Martinez-Botas, M. Seiler, and N. P. 2010. The Effect of Unequal Admission on the Performance and Loss Generation in a Double-Entry Turbocharger Turbine. Proc ASME Turbo Expo No. GT2010-22212.

C. D. Copeland, P. Newton, R. F. Martinez-Botas, and M. Seiler. 2012. A Comparison of Timescales Within a Pulsed Flow Turbocharger Turbine.10th International Conference on Turbochargers and Turbocharging. 389–404.

P. Newton, R. Martinez-Botas, and M. Seiler. 2014. A Three-Dimensional Computational Study of Pulsating Flow Inside a Double Entry Turbine. J. Turbomach.137(3): 031001.

S. Szymko. 2006. The Development of an Eddy Current Dynamometer for Evaluation of Steady and Pulsating Turbocharger Turbine Performance. Imperial College of Science, Technology and Medicine, University of London.

S. Rajoo and R. Martinez-Botas. 2006. Experimental Study on the Performance of a Variable Geometry Mixed Flow Turbine for Automotive Turbocharger. 8th International Conference on Turbochargers and Turbocharging. 183–192.

M. Abidat. 1991. Design and Testing of a Highly Loaded Mixed Flow Turbine. Imperial College of Science, Technology and Medicine, University of London.

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Published

2016-08-16

How to Cite

Padzillah, M., Rajoo, S., & Martinez-Botas, R. (2016). PRESSURE DISTRIBUTION ON THE BLADE SURFACE OF AN AUTOMOTIVE MIXED FLOW TURBOCHARGER TURBINE UNDER PULSATING FLOW CONDITIONS. Jurnal Teknologi, 78(8-4). https://doi.org/10.11113/jt.v78.9596

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Section

Science and Engineering