Notice of Retraction: Analysis of flow field and parameter optimization on the intake port of the non-road small spark-ignition engine

In this research, the residual gas, peak firing pressure increase, and effective release energy were completely investigated. To obtain this target, the experimental system is installed with a dynamo system and a simulation model was setup. Through combined experimental and simulation methods, the drawbacks of the hardware optimization method were eliminated. The results of the research show that the valve port diameter-bore ratio (VPD/B) has a significant effect on the residual gas, peak firing pressure increase, and effective release energy of a four-stroke spark ignition engine. In this research, the engine was performed at 3000 rpm and full load condition. Following increased IPD/B ratio of 0.3–0.5. The intake port and exhaust port diameter has a contrary effect on engine volumetric efficiency, the residual gas ratio increase 27.3% with larger intake port and decrease 18.6% with larger exhaust port. The engine will perform optimal thermal efficiency when the trapped residual gas fraction ratio is from 13% to 14%. The maximum effective release energy was 0.45 kJ at 0.4 intake port-bore ratio, and 0.451 kJ at 0.35 exhaust port-bore ratio. The NOx emission increases until achieved a maximum value after that decrease even VPD/B was still increasing. With a VPD/B ratio of 0.35 to 0.4, the engine works without the misfiring.

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Post-Combustion In-Cylinder Vaporization During Cranking and Startup in a Port-Fuel–Injected Spark Ignition Engine

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.2061307 ◽

2005 ◽

Vol 128 (2) ◽

pp. 397-402 ◽

Cited By ~ 7

Author(s):

Jim S. Cowart

Keyword(s):

Combustion Chamber ◽

Liquid Fuel ◽

Combustion Process ◽

Spark Ignition ◽

Liquid Films ◽

Spark Ignition Engine ◽

Fuel Vapor ◽

Intake Port ◽

Warm Up ◽

Flame Ionization

During port-fuel–injected (PFI) spark-ignition (SI) engine startup and warm-up fuel accounting continues to be a challenge. Excess fuel must be injected for a near stoichiometric combustion charge. The “extra” fuel that does not contribute to the combustion process may stay in the intake port or as liquid films on the combustion chamber walls. Some of this combustion chamber wall liquid fuel is transported to the engine’s oil sump and some of this liquid fuel escapes combustion and evolves during the expansion and exhaust strokes. Experiments were performed to investigate and quantify this emerging in-cylinder fuel vapor post-combustion cycle by cycle during engine startup. It is believed that this fuel vapor is evaporating from cylinder surfaces and emerging from cylinder crevices. A fast in-cylinder diagnostic, the fast flame ionization detector, was used to measure this behavior. Substantial post-combustion fuel vapor was measured during engine startup. The amount of post-combustion fuel vapor that develops relative to the in-cylinder precombustion fuel charge is on the order of one for cold starting (0 °C) and decreases to ∼13 for hot starting engine cycles. Fuel accounting suggests that the intake port puddle forms quickly, over the first few engine cranking cycles. Analysis suggests that sufficient charge temperature and crevice oxygen exists to at least partially oxidize the majority of this post-combustion fuel vapor such that engine out hydrocarbons are not excessive.

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An Adaptive Estimator of Fuel Film Dynamics in the Intake Port of a Spark Ignition Engine

IFAC Proceedings Volumes ◽

10.1016/s1474-6670(17)34411-7 ◽

2001 ◽

Vol 34 (1) ◽

pp. 283-288

Author(s):

I. Arsie ◽

C. Pianese ◽

G. Rizzo ◽

V. Cioffi

Keyword(s):

Spark Ignition ◽

Spark Ignition Engine ◽

Intake Port ◽

Fuel Film ◽

Adaptive Estimator

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Numerical analysis of the influence of early fuel injection on charge motion in a direct injection spark ignition engine using scale-resolving simulations

International Journal of Engine Research ◽

10.1177/1468087419860725 ◽

2019 ◽

Vol 21 (4) ◽

pp. 664-682

Author(s):

Martin Theile ◽

Martin Reißig ◽

Egon Hassel ◽

Dominique Thévenin ◽

Martin Hofer ◽

...

Keyword(s):

Numerical Analysis ◽

Flow Field ◽

Fuel Injection ◽

Direct Injection ◽

Spark Ignition ◽

Spark Ignition Engine ◽

Post Processing ◽

Charge Motion ◽

Set Up ◽

Direct Injection Spark Ignition

This work summarizes the numerical analysis of the effect of early fuel injection on the charge motion in a direct injection spark ignition engine concerning cyclic fluctuations of the flow field. The combination of the scale-resolving turbulence model “Scale Adaptive Simulation” and post-processing routines for vortex trajectory visualization allows for a detailed insight into the temporal resolved and cycle-dependent behavior of the charge motion. In the first part, a simplified engine set-up is presented and used as a validation case to ensure correct behavior of the turbulence model and post-processing routines. In the second part, the computational fluid dynamics model of the real engine is introduced. The application of the proposed vortex tracking algorithm is shown, and a short discussion about the transient behavior of the charge motion in this engine set-up is given. The third part describes the analysis of the influence of the fuel injection on the charge motion at different engine speeds from 1000 to 3000 r/min and variations of the intake pressure from 1 to 2 bar. Finally, the impact on different flow field properties at possible ignition timings is discussed. Changes in mean flow field quantities as well as in aerodynamic fluctuations are found as a consequence of fuel injection.

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