ISSN:
0271-2091
Keywords:
Turbulence
;
Rapid Compression Expansion
;
Bowl-in-piston
;
TDC
;
BDC
;
Inclined Walls
;
PHOENICS
;
Engineering
;
Engineering General
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
The paper presents two- and three-dimensional computations of the in-cylinder turbulent flow in a diesel engine. The mathematical formulation is presented first, with emphasis on the modifications made to the standard k-ε model of turbulence, to account for rapid compression/expansion, and on the k-w model also used in the computations. Then, the results of two-and three-dimensional transient calculations are presented and compared with experimental data. It is realized that two-dimensional computations may be of little value to real engines, which would probably require three-dimensional analyses. However, two-dimensional studies are still useful in allowing the testing of new ideas easily and economically. It is concluded that the standard k-ε model may lead to poor predictions when used for internal combustion (IC) engine simulations, and that the modified model leads to more reasonable length-scale distributions, and it improves significantly the overall agreement of velocity predictions with experiment. The effect of the k-ε modification is apparent in both the two- and three-dimensional simulations. It is also demonstrated that the k-w model provides better turbulence predictions than the unmodified k-ε model, for the cases considered, and that a similar modification of the k-w model, to account for rapid compression/expansion, might improve its predictions even further.
Additional Material:
22 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/fld.1650070905
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