Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Influence of upstream geometry on pulsatile turbocharger turbine performance
KTH, School of Industrial Engineering and Management (ITM), Centres, Competence Center for Gas Exchange (CCGEx). KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics.ORCID iD: 0000-0002-6090-1498
KTH, School of Engineering Sciences (SCI), Centres, Faxén Laboratory. KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics.ORCID iD: 0000-0002-2906-9306
KTH, School of Industrial Engineering and Management (ITM), Centres, Competence Center for Gas Exchange (CCGEx). KTH, School of Engineering Sciences (SCI), Centres, Linné Flow Center, FLOW. KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Physics. KTH, School of Engineering Sciences (SCI), Mechanics, Fluid Mechanics of Industrial Processes.ORCID iD: 0000-0001-7330-6965
2018 (English)Report (Other academic)
Abstract [en]

This research was primary motivated by limited efforts to understand the effects of secondary flow and flow unsteadiness on the heat transfer and the performance of a turbocharger turbine subjected to pulsatile flow. In this study, we aimed to investigate the influence of exhaust manifold on the flow physics and the performance of its downstream components, including the effects on heat transfer, under engine-like pulsatile flow conditions. Based on the predicted results by Detached Eddy Simulation (DES), qualitative and quantitative flow fields analyses in the scroll and the rotor’s inlet were performed, in addition to the quantification of turbine performance by using the flow exergy methodology. With the specified geometry configuration and exhaust valve strategy, our study showed that 1) The exhaust manifold influences the flow field and the heat transfer in the scroll significantly, and 2) Although the relative inflow angle at the rotor’s inlet is significantly affected by the initial exhaust gas blow down from the exhaust manifold, the consequence on the turbine power is relatively small.

Place, publisher, year, edition, pages
Shyang Maw Lim , 2018.
National Category
Fluid Mechanics and Acoustics
Research subject
Engineering Mechanics
Identifiers
URN: urn:nbn:se:kth:diva-238852OAI: oai:DiVA.org:kth-238852DiVA, id: diva2:1262774
Note

QC 20181113

Available from: 2018-11-12 Created: 2018-11-12 Last updated: 2018-11-14Bibliographically approved
In thesis
1. Aerothermodynamics and exergy analysis in turbocharger radial turbine
Open this publication in new window or tab >>Aerothermodynamics and exergy analysis in turbocharger radial turbine
2018 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

Coupling of turbomachine to reciprocating automotive engine in turbocharging leads to complex fluid flow and thermal characteristics in the turbine. Some undesirable characteristics include heat transfer, flow pulsation and secondary flow due to the complex geometry of the upstream exhaust manifold. The performed literature review exposed that there is a need for an enhanced understanding of the thermo-fluid physics of a turbocharger turbine operating under realistic on-engine conditions, and on quantifying the impact on the performance. Often, simplified set-ups and geometries are employed, neglecting the heat transfer.

This dissertation aimed to improve the quality of heat transfer analysis in a turbocharger turbine, and to enhance the understanding of aerothermodynamic effects due to heat transfer on the performance under engine-like pulsatile flow scenarios. Firstly, a flow exergy based analysis was developed to be used with the input provided by three-dimensional flow field data predicted by Detached Eddy Simulation (DES). Its applicability to identify and to quantify the aerothermodynamic related losses due to heat transfer was thoroughly investigated with a set-up replicating a hot gas stand continuous flow scenario. Next, the developed methodology was applied to engine-like pulsatile flow scenarios, to investigate the effects of flow pulsation and the influences of upstream exhaust manifold on the heat transfer and turbine performance. For the investigated geometry and specified boundary conditions, this dissertation mainly concluded that 1) The most sensitive measures associated with heat loss are the flow exergy lost via heat transfer and the thermal irreversibilities. The influence of heat loss on turbine power reduction is small in a relative sense, and 2) Although the exhaust manifold characteristics govern the fundamental flow physics and heat transfer in the scroll, its impact on the turbine power seems to be small relatively. 

The contributions with this dissertation were mainly twofold. Firstly, it contributes to a deeper understanding of the thermo-fluid physics of a turbocharger turbine operating under engine-like pulsating flow scenario. This knowledge might be useful for industrial product development in the future. Secondly, from academic perspective, the flow exergy budget analysis could potentially serve as a practical example to students in connecting the dots between classroom theory and real life engineering application.

Place, publisher, year, edition, pages
Stockholm: KTH Royal Institute of Technology, 2018. p. 89
Series
TRITA-SCI-FOU ; 2018:41
Keywords
pulsatile exhaust flow, turbine, turbocharger, Detached Eddy Simulation, heat transfer, exergy
National Category
Fluid Mechanics and Acoustics
Research subject
Engineering Mechanics
Identifiers
urn:nbn:se:kth:diva-238833 (URN)978-91-7729-956-1 (ISBN)
Public defence
2018-12-07, Kollegiesalen, Brinellvägen 8, Stockholm, 10:15 (English)
Opponent
Supervisors
Note

QC 20181113

Available from: 2018-11-13 Created: 2018-11-12 Last updated: 2018-11-13Bibliographically approved

Open Access in DiVA

No full text in DiVA

Authority records BETA

Lim, Shyang MawDahlkild, AndersMihaescu, Mihai

Search in DiVA

By author/editor
Lim, Shyang MawDahlkild, AndersMihaescu, Mihai
By organisation
Competence Center for Gas Exchange (CCGEx)Fluid PhysicsFaxén LaboratoryLinné Flow Center, FLOWFluid Mechanics of Industrial Processes
Fluid Mechanics and Acoustics

Search outside of DiVA

GoogleGoogle Scholar

urn-nbn

Altmetric score

urn-nbn
Total: 125 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf