Research Papers

Design and Analysis of a Novel Split Sliding Variable Nozzle for Turbocharger Turbine

[+] Author and Article Information
Liangjun Hu

Research and Innovation Center,
Ford Motor Company,
Dearborn, MI 48124
e-mail: lhu4@ford.com

Harold Sun

Research and Innovation Center,
Ford Motor Company,
Dearborn, MI 48124
e-mail: hsun3@ford.com

James Yi

Research and Innovation Center,
Ford Motor Company,
Dearborn, MI 48124
e-mail: jyi1@ford.com

Eric Curtis

Research and Innovation Center,
Ford Motor Company,
Dearborn, MI 48124
e-mail: ecurtis@ford.com

Jizhong Zhang

Diesel Engine Turbocharging Laboratory,
China North Engine Research Institute,
Tianjin 300400, China
e-mail: dtzjz@163.com

1Corresponding author.

Contributed by the International Gas Turbine Institute (IGTI) of ASME for publication in the JOURNAL OF TURBOMACHINERY. Manuscript received November 3, 2017; final manuscript received November 25, 2017; published online April 6, 2018. Editor: Kenneth Hall.

J. Turbomach 140(5), 051006 (Apr 06, 2018) (10 pages) Paper No: TURBO-17-1205; doi: 10.1115/1.4038878 History: Received November 03, 2017; Revised November 25, 2017

Variable geometry turbine (VGT) has been widely applied in internal combustion engines to improve engine transient response and torque at light load. One of the most popular VGTs is the variable nozzle turbine (VNT) in which the nozzle vanes can be rotated along the pivoting axis and thus the flow passage through the nozzle can be adjusted to match with different engine operating conditions. One disadvantage of the VNT is the turbine efficiency degradation due to the leakage flow in the nozzle endwall clearance, especially at small nozzle open condition. With the purpose to reduce the nozzle leakage flow and to improve turbine stage efficiency, a novel split sliding variable nozzle turbine (SSVNT) has been proposed. In the SSVNT design, the nozzle is divided into two parts: one part is fixed and the other part can move along the partition surface. When sliding the moving vane to large radius position, the nozzle flow passage opens up and the turbine has high flow capacity. When sliding the moving vane to small radius position, the nozzle flow passage closes down and the turbine has low flow capacity. As the fixed vane does not need endwall clearance, the leakage flow through the nozzle can be reduced. Based on calibrated numerical simulation, there is up to 12% turbine stage efficiency improvement with the SSVNT design at small nozzle open condition while maintaining the same performance at large nozzle open condition. The mechanism of efficiency improvement in the SSVNT design has been discussed.

Copyright © 2018 by ASME
Your Session has timed out. Please sign back in to continue.


Bains, N. , 1998, “ Radial and Mixed Flow Turbines Options for High Boost Turbocharger,” Seventh International Conference on Turbocharger and Turbocharging, pp. 35–44.
Watson, N. , and Janota, M. , 1982, Turbocharging the Internal Combustion Engine, Macmillan Education, New York. [CrossRef]
Rogo, C. , Hajek, T. , and Relke, R. , 1983, “Aerodynamic Effects of Moveable Sidewall Nozzle Geometry and Rotor Exit Restriction on the Performance of a Radial Turbine,” SAE Paper No. 831517.
Arnold, S. , 1987, “Schwitzer Variable Geometry Turbo and Microprocessor Control Design and Evaluation,” SAE Paper No. 870296.
Franklin, P. , 1989, “Performance Development of the Holset Variable Geometry Turbocharger,” SAE Paper No. 890646.
Kawaguchi, J. , Adachi, J. , and Kono, S. , 1999, “Development of VFT (Variable Flow Turbocharger),” SAE Paper No. 1999-01-1242.
Hayami, H. , Senoo, Y. , and Hyun, Y. , 1990, “ Effects of Tip Clearance of Nozzle Vanes on Performance of Radial Turbine Rotor,” ASME J. Turbomach., 112(1), pp. 58–63. [CrossRef]
Tamaki, H. , Goto, S. , and Unno, M. , 2010, “The Effect of Clearance Flow of Variable Area Nozzles on Radial Turbine Performance,” ASME Paper No. GT2010-23677.
Hu, L. , Yang, C. , and Sun, H. , 2011, “ Numerical Analysis of Nozzle Clearance Effect on Turbine Performance,” Chin. J. Mech. Eng., 24(4), pp. 618–625. [CrossRef]
Walkingshaw, J. , Spence, S. , and Enrhard, J. , 2012, “ An Experimental Assessment of the Effects of Stator Vane Tip Clearance Location and Back Swept Blading on an Automotive Variable Geometry Turbocharger,” ASME J. Turbomach., 226(6), pp. 751–763.
Tomoki, K. , Goto, S. , Unno, M. , and Iwakami, A. , 2008, “Unsteady Rotor-Stator Interaction of a Radial-Inflow Turbine With Variable Nozzle Vanes,” ASME Paper No. GT2008-50461.
Hu, L. , Sun, H. , Yi, J. , Curtis, E. , Morelli, A. , Zhang, J. , Zhao, B. , Yang, C. , Shi, X. , and Liu, S. , 2013, “Investigation of Nozzle Clearance Effects on a Radial Turbine: Aerodynamic Performance and Forced Response,” SAE Paper No. 2013-01-0918.
Sun, H. , Zhang, J. , and Hu, L. , 2013, “Sliding Vane Geometry Turbine,” Ford Global Technologies, LLC, Dearborn, MI, U.S. Patent No. US20130042608 A1.
NUMECA, 2014, IGG User Manual, v9, ed., NUMECA International, Brussels, Belgium. [PubMed] [PubMed]
Zhu, D. , 1992, Turbocharging and Turbochargers, China Machine Press, Beijing, China.
He, P. , Sun, Z. G. , Chen, H. S. , and Tan, C. Q. , 2012, “ Investigation of Backface Cavity Sealing Flow in Deeply Scalloped Radial Turbines,” Proc. Inst. Mech. Eng. Part A, 226(6), pp. 751–763.
Bains, N. , 2005, Fundamentals of Turbocharging, Concepts NREC, White River Junction, VT.
Arnold, S. , Groskrevtz, M. , and Shahed, S. , 2002, “Advanced Variable Geometry Turbocharger for Diesel Engine Applications,” SAE Paper No. 2002-01-0161.


Grahic Jump Location
Fig. 8

Comparison of simulated and tested turbine performance: (a) pressure ratio-mass flow and (b) pressure ratio-efficiency

Grahic Jump Location
Fig. 7

Illustration of turbocharger flow bench for turbine performance test

Grahic Jump Location
Fig. 6

Nozzle endwall clearance on the hub side

Grahic Jump Location
Fig. 5

Nozzle insert at small nozzle opening

Grahic Jump Location
Fig. 4

Mesh and CFD model of a SSVNT design

Grahic Jump Location
Fig. 3

Illustrations of nozzle clearance and leakage flow of base VNT

Grahic Jump Location
Fig. 2

Illustration of SSVNT

Grahic Jump Location
Fig. 1

Vehicle driving cycle on matched turbine map

Grahic Jump Location
Fig. 17

Rotor inlet incidence angle comparison

Grahic Jump Location
Fig. 18

Flow separation at 10% spanwise location: (a) base VNT and (b) SSVNT

Grahic Jump Location
Fig. 19

Boundary layer flow comparison on the hub and impeller suction side: (a) base VNT and (b) SSVNT

Grahic Jump Location
Fig. 20

Loading comparison between base VNT and SSVNT: (a) hub, (b) middle-span, and (c) shroud

Grahic Jump Location
Fig. 9

Different base nozzle shapes

Grahic Jump Location
Fig. 10

Partition surface design of SSVNT

Grahic Jump Location
Fig. 11

Flow loss comparisons between pressure side and suction side of the conventional VNT

Grahic Jump Location
Fig. 12

Main parameters of nozzle

Grahic Jump Location
Fig. 13

Comparison of turbine aero performance: (a) turbine mass flow and (b) turbine efficiency

Grahic Jump Location
Fig. 14

Nozzle endwall leakage flow comparison at 13% open condition: (a) base VNT and (b) SSVNT

Grahic Jump Location
Fig. 15

LFR comparison at 13% open condition

Grahic Jump Location
Fig. 16

Nozzle vane total pressure loss comparison: (a) SSVNT, (b) VNT, and (c) nozzle total pressure loss




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 Journal Articles
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