Effect of ethanol–gasoline blends on CO and HC emissions in last generation SI engines within the cold-start transient: An experimental investigation

A novel fuel atomization device (Nanomiser™) was evaluated under laboratory conditions with respect to its ability to reduce SI engine cold-start hydrocarbon emissions. First, comparisons between the level of atomization using the conventional, pintle-type fuel injector and the novel atomizer were carried out using flow visualization in a spray chamber and particle size distribution. The novel atomizer is capable of producing sub-micron fuel droplets, which form an ultra-fine mist with outstanding non-wetting characteristics. To capitalize on these atomization characteristics, this device was compared to a conventional fuel injector in a small, two-cylinder, SI engine under a number of operating conditions. Results show a slightly enhanced combustion quality and lean limit under warm operating conditions and a dramatic reduction in unburned HC emission under cold operating conditions, with cold emissions with the Nanomiser™ matching those with a conventional injector under fully warm conditions.

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Optical Investigations of Fuel-Mixture Generation at Cold Start Conditions of SI-Engines in Consideration of Heat Loading

10.4271/2011-26-0079 ◽

2011 ◽

Author(s):

Andreas Bradenstahl ◽

Andreas Broda ◽

Peter Eilts

Keyword(s):

Cold Start ◽

Fuel Mixture ◽

Heat Loading ◽

Si Engines

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Experimental investigation of the effect of thin-wall substrates and spark timing retard on total hydrocarbon emissions during cold start for super-ultra-low-emission vehicle application

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1243/095440704773599935 ◽

2004 ◽

Vol 218 (4) ◽

pp. 427-433 ◽

Cited By ~ 6

Author(s):

Cha-Lee Myung ◽

Simsoo Park ◽

Han-Sang Kim ◽

Kyoungdoug Min ◽

Myung-Sik Choi

Keyword(s):

Experimental Investigation ◽

Cold Start ◽

Hydrocarbon Emissions ◽

Thin Wall ◽

Total Hydrocarbon ◽

Spark Timing ◽

Low Emission

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Early Model-Based Design and Verification of Automotive Control System Software Implementations

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.4027845 ◽

2014 ◽

Vol 137 (2) ◽

Cited By ~ 16

Author(s):

Mahdi Shahbakhti ◽

Mohammad Reza Amini ◽

Jimmy Li ◽

Satoshi Asami ◽

J. Karl Hedrick

Keyword(s):

Controller Design ◽

Combustion Engine ◽

Control Unit ◽

Cold Start ◽

Early Model ◽

Automotive Control ◽

Model Based ◽

Numerical Noise ◽

Software Implementations ◽

Hc Emissions

Verification and validation (V&V) are essential stages in the design cycle of automotive controllers to remove the gap between the designed and implemented controller. In this paper, an early model-based methodology is proposed to reduce the V&V time and improve the robustness of the designed controllers. The application of the proposed methodology is demonstrated on a cold start emission control problem in a midsize passenger car. A nonlinear reduced order model-based controller based on singular perturbation approximation (SPA) is designed to reduce cold start hydrocarbon (HC) emissions from a spark ignition (SI) combustion engine. A model-based simulation platform is created to verify the controller robustness against sampling, quantization, and fixed-point arithmetic imprecision. In addition, the results from early model-based verification are used to identify and remove sources of errors causing propagation of numerical imprecision in the controller structure. Thus the structure of the controller is modified to avoid or to reduce the level of numerical noise in the controller design. The performance of the final modified controller is validated in real-time by testing the control algorithm on a real engine control unit. The validation results indicate the modified controller is 17–63% more robust to different implementation imprecision while it requires lower implementation cost. The proposed methodology from this paper is expected to reduce typical V&V efforts in the development of automotive controllers.

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An Experimental Study of a Fluidic Type Fuel Injector in Comparison With a Solenoid Type Injector

Proceedings of the Institution of Mechanical Engineers Part D Journal of Automobile Engineering ◽

10.1243/pime_proc_1996_210_254_02 ◽

1996 ◽

Vol 210 (2) ◽

pp. 131-147

Author(s):

Q Huang ◽

D P Sansum

Keyword(s):

Experimental Study ◽

Injection System ◽

Fuel Injector ◽

Indicated Mean Effective Pressure ◽

Fuel Delivery ◽

Fluidic Device ◽

Si Engines ◽

Lean Misfire Limit ◽

Hc Emissions ◽

Type Fuel

An experimental study of a fluidic type fuel injector for spark ignition (SI) engines is described in this paper. The fluidic injector unit consists of four monostable fluidic devices controlled by a solenoid interface and air–fuel mixing nozzles for better fuel atomization. The prototype fluidic injector unit was implemented on a research engine. The results of air–fuel ratio (AFR) variations, engine combustion characteristics and exhaust emissions from the fluidic injector were compared with those from a baseline solenoid type injector. It was demonstrated from single cylinder engine tests that the fluidic system produces 9 to 20 per cent lower hydrocarbon (HC) emissions and 5 to 8 per cent higher indicated mean effective pressure (IMEP) than the baseline injection system. This has confirmed the effectiveness of the use of air-assisted fluidic injectors and the fact that improved mixture preparation and better fuel presentation are obtained by the fluidic injector. However, the lean misfire limit by the fluidic injector is reduced by 1 AFR compared to that of the solenoid injector due to large AFR dispersions caused by cyclic fuel delivery variations of the fluidic device. It is envisaged that the fluidic injector potentially offers cost and emission benefits for SI engines when the cyclic flow stability is improved.

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