Pulse performance modeling of a twin entry turbocharger turbine under full and unequal admission

Aaron W. Costall, Robert M. McDavid, Ricardo F. Martinez-Botas, Nicholas C. Baines

Research output: Chapter or section in a book/report/conference proceedingChapter in a published conference proceeding

17 Citations (SciVal)


The pulsating nature of the gas flow within the exhaust manifold of an internal combustion engine is not well captured by the quasi-steady techniques typically employed by cycle simulation programs for turbocharger modeling. This problem is compounded by the unequal admission conditions imposed on the turbine by the use of multiple entry housings, installed as standard on pulse turbocharged diesel engines. This unsteady behavior presents the simulation engineer with a unique set of difficulties when modeling turbocharger turbines. It is common for experienced analysts to accommodate multiple entries by splitting the flow across duplicate components and by tuning the level of interference between volute entries, but this necessarily bespoke approach is limited to upstream modifications that cannot capture true turbine unsteady operation. This paper describes recent simulation code development work undertaken at Caterpillar to improve machine sub-model accuracy essential for virtual product development meeting US nonroad Tier 4 emission standards. The resulting turbine performance model has been validated against experimental data for a twin entry turbocharger suitable for heavy duty nonroad applications, obtained using a permanent magnet eddy-current dynamometer and pulse flow test facility. Comparison between experiment and prediction demonstrates good agreement under full admission in terms of both instantaneous flow capacity and turbine actual power, though unequal admission results indicate the need for further model development.

Original languageEnglish
Title of host publicationProceedings of the ASME Turbo Expo 2009
Subtitle of host publicationPower for Land, Sea and Air
Number of pages12
EditionPART B
Publication statusPublished - 2009
Event2009 ASME Turbo Expo - Orlando, FL, USA United States
Duration: 8 Jun 200912 Jun 2009

Publication series

NameProceedings of the ASME Turbo Expo
NumberPART B


Conference2009 ASME Turbo Expo
Country/TerritoryUSA United States
CityOrlando, FL

ASJC Scopus subject areas

  • Engineering(all)


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