Radial Gradient Pressure Effects on Flow Behavior in a Dual Volute Turbocharger Turbine

Azadeh Sajedin, Mohammad Hasan Shojaeefard, Abolfazl Khalkhali

Research output: Contribution to journalArticle

Abstract

The pressure gradient in the dual volute radial turbocharger turbines is the primary source of the vortices’ formation in rotor passages. The effects of the upstream non-uniform flow conditions on the development of secondary flows are not well known. In this study, the effect of highly skewed and non-uniform mass flow on the secondary vortices in different admission cases in a dual entry turbine was investigated using CFD modeling. The results agree well with the experiment, and show that increasing the inequality of the pressure between the entries leads to a reduction in the turbine’s performance. Some useful energy dissipates due to mixing the flows of the entries. Isolating the rotor sectors in the tongues region was applied with the purpose of limiting the mixing. Also, the vortices’ behavior in the rotor passages with different surface pressure ratios for the passage sides were investigated for both equal and partial admission. The surface pressure of the airfoil pressure side was more effective on the tip and trailing edge vortex than the suction side, while the leading-edge root vortex did not change by any variation in the surface pressure ratio. The vortices’ center location shifted with the pressure variation, and consequently, by decreasing the pressure level, the center of the tip vorticity turned to the upstream sections, and the leading-edge root vortex center moved closer to the pressure side.
Original languageEnglish
Article number1961
Number of pages15
JournalApplied Sciences (Switzerland)
Volume8
Issue number10
DOIs
Publication statusPublished - 17 Oct 2018
Externally publishedYes

Fingerprint

turbochargers
Pressure effects
turbines
pressure effects
Turbines
Vortex flow
gradients
vortices
entry
rotors
pressure ratio
Rotors
leading edges
upstream
nonuniform flow
secondary flow
tongue
trailing edges
airfoils
Secondary flow

Cite this

Sajedin, Azadeh ; Shojaeefard, Mohammad Hasan ; Khalkhali, Abolfazl . / Radial Gradient Pressure Effects on Flow Behavior in a Dual Volute Turbocharger Turbine. In: Applied Sciences (Switzerland). 2018 ; Vol. 8, No. 10.
@article{58bbf6e3796b4646a2babcdc03af0c1e,
title = "Radial Gradient Pressure Effects on Flow Behavior in a Dual Volute Turbocharger Turbine",
abstract = "The pressure gradient in the dual volute radial turbocharger turbines is the primary source of the vortices’ formation in rotor passages. The effects of the upstream non-uniform flow conditions on the development of secondary flows are not well known. In this study, the effect of highly skewed and non-uniform mass flow on the secondary vortices in different admission cases in a dual entry turbine was investigated using CFD modeling. The results agree well with the experiment, and show that increasing the inequality of the pressure between the entries leads to a reduction in the turbine’s performance. Some useful energy dissipates due to mixing the flows of the entries. Isolating the rotor sectors in the tongues region was applied with the purpose of limiting the mixing. Also, the vortices’ behavior in the rotor passages with different surface pressure ratios for the passage sides were investigated for both equal and partial admission. The surface pressure of the airfoil pressure side was more effective on the tip and trailing edge vortex than the suction side, while the leading-edge root vortex did not change by any variation in the surface pressure ratio. The vortices’ center location shifted with the pressure variation, and consequently, by decreasing the pressure level, the center of the tip vorticity turned to the upstream sections, and the leading-edge root vortex center moved closer to the pressure side.",
keywords = "double volute entry, different admission, radial turbine, turbocharger, vortical flow",
author = "Azadeh Sajedin and Shojaeefard, {Mohammad Hasan} and Abolfazl Khalkhali",
year = "2018",
month = "10",
day = "17",
doi = "10.3390/app8101961",
language = "English",
volume = "8",
journal = "Applied Sciences (Switzerland)",
issn = "2076-3417",
publisher = "MDPI",
number = "10",

}

Radial Gradient Pressure Effects on Flow Behavior in a Dual Volute Turbocharger Turbine. / Sajedin, Azadeh; Shojaeefard, Mohammad Hasan; Khalkhali, Abolfazl .

In: Applied Sciences (Switzerland), Vol. 8, No. 10, 1961, 17.10.2018.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Radial Gradient Pressure Effects on Flow Behavior in a Dual Volute Turbocharger Turbine

AU - Sajedin, Azadeh

AU - Shojaeefard, Mohammad Hasan

AU - Khalkhali, Abolfazl

PY - 2018/10/17

Y1 - 2018/10/17

N2 - The pressure gradient in the dual volute radial turbocharger turbines is the primary source of the vortices’ formation in rotor passages. The effects of the upstream non-uniform flow conditions on the development of secondary flows are not well known. In this study, the effect of highly skewed and non-uniform mass flow on the secondary vortices in different admission cases in a dual entry turbine was investigated using CFD modeling. The results agree well with the experiment, and show that increasing the inequality of the pressure between the entries leads to a reduction in the turbine’s performance. Some useful energy dissipates due to mixing the flows of the entries. Isolating the rotor sectors in the tongues region was applied with the purpose of limiting the mixing. Also, the vortices’ behavior in the rotor passages with different surface pressure ratios for the passage sides were investigated for both equal and partial admission. The surface pressure of the airfoil pressure side was more effective on the tip and trailing edge vortex than the suction side, while the leading-edge root vortex did not change by any variation in the surface pressure ratio. The vortices’ center location shifted with the pressure variation, and consequently, by decreasing the pressure level, the center of the tip vorticity turned to the upstream sections, and the leading-edge root vortex center moved closer to the pressure side.

AB - The pressure gradient in the dual volute radial turbocharger turbines is the primary source of the vortices’ formation in rotor passages. The effects of the upstream non-uniform flow conditions on the development of secondary flows are not well known. In this study, the effect of highly skewed and non-uniform mass flow on the secondary vortices in different admission cases in a dual entry turbine was investigated using CFD modeling. The results agree well with the experiment, and show that increasing the inequality of the pressure between the entries leads to a reduction in the turbine’s performance. Some useful energy dissipates due to mixing the flows of the entries. Isolating the rotor sectors in the tongues region was applied with the purpose of limiting the mixing. Also, the vortices’ behavior in the rotor passages with different surface pressure ratios for the passage sides were investigated for both equal and partial admission. The surface pressure of the airfoil pressure side was more effective on the tip and trailing edge vortex than the suction side, while the leading-edge root vortex did not change by any variation in the surface pressure ratio. The vortices’ center location shifted with the pressure variation, and consequently, by decreasing the pressure level, the center of the tip vorticity turned to the upstream sections, and the leading-edge root vortex center moved closer to the pressure side.

KW - double volute entry

KW - different admission

KW - radial turbine

KW - turbocharger

KW - vortical flow

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85055107203&origin=inward&txGid=cd12577a2819d00657e8ac502f1a3875

U2 - 10.3390/app8101961

DO - 10.3390/app8101961

M3 - Article

VL - 8

JO - Applied Sciences (Switzerland)

JF - Applied Sciences (Switzerland)

SN - 2076-3417

IS - 10

M1 - 1961

ER -