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Research Papers: Gas Turbines: Combustion, Fuels, and Emissions

A Comparison of Valving Strategies Appropriate For Multimode Combustion Within a Downsized Boosted Automotive Engine—Part I: High Load Operation Within the Spark Ignition Combustion Regime

[+] Author and Article Information
Prasad S. Shingne

Mem. ASME
Walter E. Lay Automotive Laboratory,
University of Michigan,
1231 Beal Avenue,
Ann Arbor, MI 48109
e-mail: sunand@umich.edu

Matthew S. Gerow

Walter E. Lay Automotive Laboratory,
University of Michigan,
1231 Beal Avenue,
Ann Arbor, MI 48109
e-mail: matthewsgerow@gmail.com

Vassilis Triantopoulos

Walter E. Lay Automotive Laboratory,
University of Michigan,
1231 Beal Avenue,
Ann Arbor, MI 48109
e-mail: vtrianto@umich.edu

Stanislav V. Bohac

Walter E. Lay Automotive Laboratory,
University of Michigan,
1231 Beal Avenue,
Ann Arbor, MI 48109
e-mail: sbohac@umich.edu

Jason B. Martz

Walter E. Lay Automotive Laboratory,
University of Michigan,
1231 Beal Avenue,
Ann Arbor, MI 48109
e-mail: jmartz@umich.edu

1Corresponding author.

Contributed by the Combustion and Fuels Committee of ASME for publication in the JOURNAL OF ENGINEERING FOR GAS TURBINES AND POWER. Manuscript received February 14, 2014; final manuscript received March 23, 2014; published online May 2, 2014. Editor: David Wisler.

J. Eng. Gas Turbines Power 136(10), 101507 (May 02, 2014) (10 pages) Paper No: GTP-14-1094; doi: 10.1115/1.4027359 History: Received February 14, 2014; Revised March 23, 2014

As future downsized boosted engines may employ multiple combustion modes, the goal of the current work is the definition of valving strategies appropriate for moderate to high load spark ignition (SI) combustion and at low to moderate loads for spark assisted compression ignition (SACI) combustion for an engine with variable valve timing capability and fixed camshaft profiles. The dilution and unburned gas temperature requirements for SACI combustion can be markedly different from those of SI; therefore it is important to ensure that a given valving strategy is appropriate for operation within both regimes. This paper compares one-dimensional (1D) thermodynamic simulations of rated engine operation with positive valve overlap (PVO) and a baseline negative valve overlap (NVO) camshaft design in a boosted automotive engine with variable valve timing capability. Several peak lifts and valve open durations are investigated to guide the down-selection of camshaft profiles for further evaluation under SACI conditions in a companion paper. While the results of this study are engine specific, rated performance predictions show that the duration of both the intake and exhaust camshafts significantly impacts the ability to achieve high load operation. While it was noted that the flow through the exhaust valves chokes for the majority of the exhaust stroke for peak exhaust lifts less than 8 mm, the aggressive engine rating of 194 kW at 5250 rpm could be achieved with peak intake lifts as low as 4 mm and baseline duration. Therefore, camshafts with peak lifts of 8/4 mm exhaust/intake were down-selected to facilitate multimode combustion operation with high levels of PVO. Analysis of high load operation with the down-selected camshafts indicates that peak unburned gas temperatures remain low enough to mitigate end-gas knock, while other variables such as peak cylinder pressure, turbine inlet temperature, and turbocharger speed are all predicted to be within acceptable limits.

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References

Olesky, L. M., Martz, J. B., Lavoie, G. A., Vavra, J., Assanis, D. N., and Babajimopoulos, A., 2013, “The Effects of Spark Timing, Unburned Gas Temperature, and Negative Valve Overlap on the Rates of Stoichiometric Spark Assisted Compression Ignition Combustion,” Appl. Energy, 105, pp. 407–417. [CrossRef]
Li, L., Xie, H., Chen, T., Yu, W., and Zhao, H., 2012, “Experimental Study on Spark Assisted Compression Ignition (SACI) Combustion With Positive Valve Overlap in a HCCI Gasoline Engine,” SAE Paper No. 2012-01-1126. [CrossRef]
GT-Suite V7.2, 2011, Gamma Technologies, Inc., Westmont, IL, http://www.gtisoft.com
“Engine Performance Application Manual,” Version 7.2, 2011, Gamma Technologies, Inc., Westmont, IL.
Heywood, J. B., 1988, Internal Combustion Engine Fundamentals, McGraw-Hill, New York, Vol. 930.
Ghojel, J. I., 2010, “Review of the Development and Applications of the Wiebe Function: A Tribute to the Contribution of Ivan Wiebe to Engine Research,” Int. J. Eng. Res., 11(4), pp. 297–312. [CrossRef]
Woschni, G., 1967, “A Universally Applicable Equation for the Instantaneous Heat Transfer Coefficient in the Internal Combustion Engine,” SAE Paper No. 670931. [CrossRef]
Chen, S. K., and Flynn, P. F., 1965, “Development of a Single Cylinder Compression Ignition Research Engine,” SAE Paper No. 650733. [CrossRef]
Lavoie, G., Ortiz-Soto, A. E., Babajimopoulos, A., Martz, J. B., and Assanis, D. N., 2013, “Thermodynamic Sweet Spot for High-Efficiency, Dilute, Boosted Gasoline Engines,” Int. J. Eng. Res., 14(3), pp. 260–278. [CrossRef]
Gerow, M. S., Shingne, P. S., Triantopoulos, V., Bohac, S. V., and Martz, J. B., 2014, “A Comparison of Valving Strategies Appropriate for Multimode Combustion Within a Downsized Boosted Automotive Engine—Part II: Midload Operation Within the SACI Combustion Regime,” ASME J. Eng. Gas Turbines Power136(10), p. 101509. [CrossRef]
Caton, J. A., 2011, “Comparisons of Global Heat Transfer Correlations for Conventional and High Efficiency Reciprocating Engines,” ASME Paper No. ICEF2011-60017. [CrossRef]
Livengood, J. C., and Wu, P. C., 1955, “Correlation of Autoignition Phenomena in Internal Combustion Engines and Rapid Compression Machines,” Symp. (Int.) Combust., 5(1), pp. 347–356. [CrossRef]
He, X., Donovan, M. T., Zigler, B. T., Palmer, T. R., Walton, S. M., Wooldridge, M. S., and AtreyamA., 2005, “An Experimental and Modeling Study of Iso-Octane Ignition Delay Times Under Homogeneous Charge Compression Ignition Conditions,” Combust. Flame, 142(3), pp. 266–275. [CrossRef]
Babajimopoulos, A., Prasad Challa, V. S. S., Lavoie, G. A., and Assanis, D. N., 2009, “Model-Based Assessment of Two Variable Cam Timing Strategies for HCCI Engines: Recompression vs. Rebreathing,” ASME Paper No. ICES2009-76103. [CrossRef]
Manofsky, L., Vavra, J., Assanis, D., and Babajimopoulos, A., 2011, “Bridging the Gap Between HCCI and SI: Spark-Assisted Compression Ignition,” SAE Paper No. 2011-01-1179. [CrossRef]
Lucht, R., Richard, P., Teets, E., Green, R. M., Palmer, R. E., and Ferguson, C. R., 1987, “Unburned Gas Temperatures in an Internal Combustion Engine. I: CARS Temperature Measurements,” Combust. Sci. Technol., 55(1), pp. 41–61. [CrossRef]
Hamamoto, Y., Tomita, E., and Jiang, D., 1994, “Temperature Measurement of End Gas Under Knocking Condition in a Spark-Ignition Engine by Laser Interferometry,” JSAE Rev., 15(2), pp. 117–122. [CrossRef]

Figures

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Fig. 1

Schematic of the engine model configuration

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Fig. 2

Simulated (a) air mass flow rate and (b) gross IMEP versus experimental data over various operating conditions. Open markers—experimental burn, closed markers—fixed burn.

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Fig. 3

Simulated (a) PMEP and (b) net IMEP versus experimental data over various operating conditions. Open markers—experimental burn, closed markers—fixed burn.

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Fig. 4

Simulated (a) intake and (b) exhaust manifold pressures versus experimental data over various operating conditions. Open markers—experimental burn, closed markers—fixed burn.

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Fig. 5

Simulated (a) fuel–air equivalence ratio and (b) exhaust temperature versus experimental data over various operating conditions. Open markers—experimental burn, closed markers—fixed burn.

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Fig. 6

Gross thermal efficiency versus gross IMEP for simulation results compared versus experimental data over various operating conditions. Thin open markers—experimental values, thick open makers—simulation with experimental burn, filled markers—simulation with fixed burn.

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Fig. 7

(a) Unburned gas temperature at TDC and (b) burned gas temperature @ 40 deg CA aTDC as function of ϕ′ over various operating conditions. Open markers—experimental burn, closed markers—fixed burn.

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Fig. 8

Location of autoignition from burn profiles and knock integral predictions as a function of unburned gas temperature at autoignition for points with 0.4 ≤ ϕ′ ≤ 0.75. Small open markers—experimental AI, large open markers—AI by knock integral using experimental burn profile, and filled markers—AI by knock integral using fixed burn profile.

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Fig. 9

(a) Intake valve lift sweep with proportional short duration—intake short (IS). (b) Exhaust valve lift sweep with proportional short duration—exhaust short (ES). (c) Intake valve lift sweep with baseline long duration—intake long (IL). (d) Exhaust valve lift sweep with baseline long duration—exhaust long (EL). (e) Intake and exhaust valve lift sweep with proportional short duration—intake short, exhaust short (IS,ES). (f) Intake and exhaust valve lift sweep with baseline long duration—intake long, exhaust long (IL,EL).

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Fig. 10

NVO (33) and proposed multimode combustion (MMC) (34) camshaft lifts

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Fig. 11

Variation of (a) air mass flow rate and (b) IMEPg with peak lifts

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Fig. 12

Variation of mean pressure difference across (a) intake and (b) exhaust valves at maximum lifts as a function of peak lifts

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Fig. 13

Variation of fraction of choked flow event for (a) intake and (b) exhaust peak lifts

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Fig. 14

Log P – Log V curves for select cases: (a) baseline (case 1), case 5, and case 9, and (b) baseline (case 1), case 16, and case 22

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Fig. 15

Variation of (a) PMEP and (b) BMEP with peak lifts

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Fig. 16

Variation of (a) turbine inlet temperatures and (b) unburned gas temperature at TDC with peak lifts

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