A multicode approach, based on the simultaneous use of zero-dimensional, one-dimensional, and three-dimensional models, has been developed and tested, and is here applied to predict the thermodynamic and fluid dynamic phenomena that characterize the unsteady gas flow propagation along the exhaust system of a turbocharged four-cylinder engine. The investigation is carried out by applying each model in a different region of the geometry, allowing to obtain detailed information of the flow behavior in complex elements, such as junctions, avoiding the significant limitations that a one-dimensional scheme always introduces, as well as fast processing typical of one-dimensional and zero-dimensional models, devoted to the analysis of ducts and volumes. The effect of the influence of different configurations of the exhaust system on the engine performance is analyzed.

1.
Capobianco, M., Gambarotta, A., and Cipolla, G., 1989, “Influence of the Pulsating Flow Operation on the Turbine Characteristics of a Small Internal Combustion Engine Turbocharger,” I. Mech. E., Paper No. C372/019.
2.
Capobianco, M., Gambarotta, A., and Cipolla, G., 1990, “Effect of Inlet Pulsating Pressure Characteristics on Turbine Performance of an Automotive Wastegated Turbocharger,” SAE Paper No. 900359.
3.
Capobianco, M., and Gambarotta, A., 1993, “Performance of a Twin-Entry Automotive Turbocharger Turbine,” ASME Paper No. 93-ICE-2.
4.
Yeo, J. H., and Baines, N. C., 1990, “Pulsating Flow Behavior in a Twin-Entry Vaneless Radial-Inflow Turbine,” I. Mech. E., Paper No. C405/004.
5.
Capobianco, M., Gambarotta, A., and Zamboni, G., 1996, “Experimental Characterization of Turbocharging and EGR Systems in an Automotive Diesel Engine,” I. Mech. E., Paper No. C517/027.
6.
Capobianco, M., Gambarotta, A., and Zamboni, G., 1998, “Controlling Turbocharging and EGR System to Improve Exhaust Aftertreatment Conditions in an Automotive Diesel Engine,” I. Mech. E., Paper No. C554/004.
7.
Trenc
,
F.
,
Bizjan
,
F.
, and
Hribernik
,
A.
,
1998
, “
Influence of the Exhaust System on Performance of a 4-Cylinder Supercharged Engine
,”
ASME J. Eng. Gas Turbines Power
,
120
, pp.
855
860
.
8.
Rakopoulos
,
C. D.
,
Andritsakis
,
E. C.
,
Hountalas
,
D. T.
,
1995
, “
The Influence of the Exhaust System Unsteady Gas Flow and Insulation on the Performance of a Turbocharged Diesel Engine
,”
Heat Recovery Syst. CHP
,
15
, No.
1
, pp.
51
72
.
9.
Onorati, A., Winterbone, D. E., and Pearson, R. J., 1993, “Comparison of the Lax-Wendroff Technique and the Method of Characteristics for Engine Gas Dynamic Calculations Using Fast Fourier Transform Spectra Analysis,” SAE Paper No. 930428.
10.
Winterbone, D. E., Nikpour, B., and Frost, H., 1991, “A Contribution to the Understanding of Turbocharger Turbine Performance in Pulsating Flow,” I. Mech. E., Paper No. C433/011.
11.
Benson, R. S., 1974, “Nonsteady Flow in a Turbocharger Nozzleless Radial Gas Turbine,” SAE Paper No. 740739.
12.
Chen, H., and Winterbone, D. E., 1990, “A Method to Predict Performance of Vaneless Radial Turbines Under Steady and Unsteady Flow Conditions,” I. Mech. E., Paper No. C405/008.
13.
Chiavola, O., 1999, “Sviluppo di modelli di simulazione delle prestazioni fluidodinamiche ed acustiche dei condotti di aspirazione e scarico di motori a combustione interna alternativi,” Ph.D. thesis, University ‘La Sapienza,’ Rome.
14.
Chiatti, G., and Chiavola, O., 1999, “Exhaust Flow Modelling in Multi-cylinder Engine by Coupling 3D FIRE With 1D Gasdynamic Code,” CDF User Meeting, AVL LIST GmbH, Graz.
15.
FIRE Manual, 1997, version 6.2.b, AVL LIST, GmbH Graz.
16.
Chiatti, G., and Chiavola, O., 1999, “Integrated 3D and 1D Modelling of Ice Exhaust Systems Flow,” 5th International Conference on High Tech Cars and Engine, Modena.
17.
Chiatti, G., and Chiavola, O., 1999, “Coupling 1D and 3D Gasdynamic Schemes to Model Engine Intake and Exhaust Systems,” ISABE XIV, Florence.
18.
Mouro, J., and Raulot, A., 1997, “Coupling of a 1D Gasdynamics Code With FIRE,” Proceedings of 3rd International FIRE User Meeting, AVL LIST GmbH, Graz.
19.
Prenninger, P., and Bartsch, P., 1997, “Application of AVL-BOOST-FIRE-Hybrid Calculation in Engine Optimization,” Proceedings of 3rd International FIRE User Meeting, AVL LIST GmbH, Graz.
20.
Onorati, A., 1995, “Numerical Simulation of Exhaust Flows and Tailpipe Noise of a Small Single Cylinder Diesel Engine,” Proceedings of the SETC, Mecca, Milwaukee, WI.
21.
Fu
,
H.
,
Tindal
,
M. J.
,
Watkins
,
A. P.
, and
Yianneskis
,
M.
,
1992
, “
Computation of Three-Dimensional Turbulent Flows in a Pipe Junction With Reference to Engine Inlet Manifolds
,”
Proc. Inst. Mech. Eng.
,
206
, pp.
285
296
.
22.
Gori, A., Sassi, L., and Bidini, G., 1995, “Analisi 3D del flusso in giunzioni di condotti di scarico,” ATA vol. 48, No. 10, pp. 508–515.
You do not currently have access to this content.