0
Research Papers

Unsteady Performance of a Double Entry Turbocharger Turbine With a Comparison to Steady Flow Conditions

[+] Author and Article Information
Colin D. Copeland

Department of Mechanical Engineering, Imperial College London, London SW7 2AZ, United Kingdomc.copeland@imperial.ac.uk

Ricardo Martinez-Botas1

Department of Mechanical Engineering, Imperial College London, London SW7 2AZ, United Kingdomr.botas@imperial.ac.uk

Martin Seiler

 ABB Turbo Systems Limited, Baden CH-5401, Switzerlandmartin.a.seiler@ch.abb.com

1

Corresponding author.

J. Turbomach. 134(2), 021022 (Jun 30, 2011) (10 pages) doi:10.1115/1.4003171 History: Received February 16, 2009; Revised March 24, 2009; Published June 30, 2011; Online June 30, 2011

Circumferentially divided, double entry turbocharger turbines are designed with a dividing wall parallel to the machine axis such that each entry feeds a separate 180 deg section of the nozzle circumference prior to entry into the rotor. This allows the exhaust pulses originating from the internal combustion exhaust to be preserved. Since the turbine is fed by two separate unsteady flows, the phase difference between the exhaust pulses entering the turbine rotor will produce a momentary imbalance in the flow conditions around the periphery of the turbine rotor. This research seeks to provide new insight into the impact of unsteadiness on turbine performance. The discrepancy between the pulsed flow behavior and that predicted by a typical steady flow performance map is a central issue considered in this work. In order to assess the performance deficit attributable to unequal admission, the steady flow conditions introduced in one inlet were varied with respect to the other. The results from these tests were then compared with unsteady, in-phase and out-of-phase pulsed flows most representative of the actual engine operating condition.

Copyright © 2012 by American Society of Mechanical Engineers
Your Session has timed out. Please sign back in to continue.

References

Figures

Grahic Jump Location
Figure 1

Circumferentially divided, double-entry turbocharger turbine

Grahic Jump Location
Figure 2

Test facility layout

Grahic Jump Location
Figure 3

Steady, equal admission relative efficiency versus velocity ratio for different constant speed lines

Grahic Jump Location
Figure 4

Steady, equal admission relative mass parameter versus pressure ratio for different constant speed lines

Grahic Jump Location
Figure 5

Performance of the turbine operating with unequal, steady flows as a percentage of peak, equal admission efficiency. Plotted against the inlet ratio of pressures.

Grahic Jump Location
Figure 6

Unequal, isentropic flow area relative to the equal admission flow area. Plotted against the inlet ratio of pressures.

Grahic Jump Location
Figure 7

Out-of-phase and in-phase absolute pressure pulses prior to nozzle (100% speed)

Grahic Jump Location
Figure 8

Comparison between cycle-averaged, unsteady and steady performances referenced to peak steady-state turbine efficiency

Grahic Jump Location
Figure 9

3D plot of steady equal and unequal relative efficiencies

Grahic Jump Location
Figure 10

Unequal, steady interpolated map. 50% and 70% unsteady traces superimposed.

Grahic Jump Location
Figure 11

Equal, steady interpolated map. 50% and 70% unsteady traces superimposed.

Grahic Jump Location
Figure 12

Unequal, steady interpolated map. 100% unsteady traces superimposed.

Grahic Jump Location
Figure 13

Equal, steady interpolated map. 100% unsteady traces superimposed.

Grahic Jump Location
Figure 14

In-phase, unsteady mass parameter versus pressure ratio: (a) 50%, 33 Hz, (b) 70%, 46 Hz, and (c) 100%, 66 Hz

Grahic Jump Location
Figure 15

Out-of-phase, unsteady mass parameter versus pressure ratio: (a) 50%, 33 Hz, (b) 70%, 46 Hz, and (c) 100%, 66 Hz

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In