Research Papers: Gas Turbines: Microturbines and Small Turbomachinery

A Comparison of a Mono-, Twin-, and Double-Scroll Turbine for Automotive Applications

[+] Author and Article Information
Jason Walkingshaw

IHI Charging Systems International,
Heidelberg 69126, Germany
e-mail: j.walkingshaw@ihi-csi.de

Georgios Iosifidis

IHI Charging Systems International,
Heidelberg 69126, Germany
e-mail: g.iosifidis@ihi-csi.de

Tobias Scheuermann

IHI Charging Systems International,
Heidelberg 69126, Germany
e-mail: t.scheuermann@ihi-csi.de

Dietmar Filsinger

IHI Charging Systems International,
Heidelberg 69126, Germany
e-mail: d.filsinger@ihi-csi.de

Nobuyuki Ikeya

Vehicular Turbocharger Operations,
IHI Corporation,
Yokohama 235-8501, Japan
e-mail: nobuyuki_ikeya@ihi.co.jp

Contributed by the Turbomachinery Committee of ASME for publication in the JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER. Manuscript received July 14, 2015; final manuscript received August 21, 2015; published online November 3, 2015. Editor: David Wisler.

J. Eng. Gas Turbines Power 138(5), 052301 (Nov 03, 2015) (10 pages) Paper No: GTP-15-1294; doi: 10.1115/1.4031449 History: Received July 14, 2015; Revised August 21, 2015

As a means of meeting ever increasing emissions and fuel economy demands, car manufacturers are using aggressive engine downsizing. To maintain the power output of the engine, turbocharging is typically used. Due to the mismatch of the mass flow characteristics of the engine to the turbocharger, at low engine mass flow rates (MFRs), the turbocharger can suffer from slow response known as “Turbolag.” Mono-scroll turbines are capable of providing good performance at high MFRs and in conjunction with low inertia mixed flow turbines can offer some benefits for transient engine response. With a multi-entry system, the individual volute sizing can be matched to the single mass flow pulse from the engine cylinders. The exhaust pulse energy can be better utilized by the turbocharger turbine improving turbocharger response, while the interaction of the engine exhaust pulses can be better avoided, improving the scavenging of the engine. The behavior of a mono-scroll turbocharger with the engine using engine simulation tools has been well established. What requires further investigation is the comparison with multi-entry turbines. Computational fluid dynamics (CFD) has been used to examine the single-admission behavior of a twin- and double-scroll turbine. Turbocharger gas stand maps of the multi-entry turbines have been measured at full and single admissions. This data have been used in a 0D engine model. In addition, the turbine stage has been tested on the engine, and a validation of the engine model against the engine test data is presented. Using the validated engine model, a comparison has been made to understand the differences in the sizing requirements of the turbine and the interaction of the mono-scroll and multi-entry turbines with the engine. The impact of the different efficiency and MFR trends of the mono and multi-entry turbochargers is discussed, and the tradeoffs between the design configurations regarding on-engine behavior are investigated.

Copyright © 2016 by ASME
Your Session has timed out. Please sign back in to continue.



Grahic Jump Location
Fig. 1

(a) Mono-scroll, (b) twin-scroll, and (c) double-scroll

Grahic Jump Location
Fig. 2

PR interaction map for twin- and double-scrolls (see Fig. 18 for key)

Grahic Jump Location
Fig. 3

Compressor map with engine working lines for each simulated turbine configuration

Grahic Jump Location
Fig. 4

Impact of CFD predicted turbine stage performance due to turbine wheel and tongue clocking

Grahic Jump Location
Fig. 5

Comparison of measured and predicted in-cylinder pressure trace for double-scroll

Grahic Jump Location
Fig. 6

Comparison of fast response pressure measurements with simulated values for double-scroll

Grahic Jump Location
Fig. 7

MFP of turbine stages required to achieve the target engine power

Grahic Jump Location
Fig. 8

Engine cycle of twin- and double-scroll configurations plotted on turbine volute interaction map—power point

Grahic Jump Location
Fig. 9

Mach number plots at PR3.2 of (a) twin-scroll (b)double-scroll—single admission

Grahic Jump Location
Fig. 10

Engine cycle of twin- and double-scroll configurations plotted on turbine volute interaction map—torque point

Grahic Jump Location
Fig. 11

Mach number in active region of double-scroll rotor exducer during the engine cycle—torque point

Grahic Jump Location
Fig. 12

% Change in time to torque for different turbine stages

Grahic Jump Location
Fig. 13

Schematic of SC concept

Grahic Jump Location
Fig. 14

Pressure–volume diagram for the different turbine configurations—power point

Grahic Jump Location
Fig. 15

Turbine exducer Mach number plot—Double-scroll: (a)no SC and (b) with SC

Grahic Jump Location
Fig. 16

Turbine performance parameters of double-scroll with and without SC at engine torque point

Grahic Jump Location
Fig. 17

Comparison of how the engine working line changes on a double-scroll without and with SC

Grahic Jump Location
Fig. 18

Possible flow scenarios for twin- and double-scrolls: (a) MFR14 = MFR23 (Beta = 1), (b)MFR23 = 0 (Beta = 0), (c) MFR14 > MFR23 (0 < Beta > 1), and (d) MFR23 < 0

Grahic Jump Location
Fig. 19

Engine performance parameters




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