Measurements of Intake Port Fuel/Air Mixture Preparation

1997 ◽  
Author(s):  
B. E. Holthaus ◽  
R. M. Wagner ◽  
J. A. Drallmeier
1999 ◽  
Author(s):  
Jiro Senda ◽  
Masanori Ohnishi ◽  
Tomohiro Takahashi ◽  
Hajime Fujimoto ◽  
Atsushi Utsunomiya ◽  
...  

1996 ◽  
Author(s):  
N. E. Carabateas ◽  
A. M. K. P. Taylor ◽  
J. H. Whitelaw ◽  
Kiyoshi Ishii ◽  
Kazuo Yoshida ◽  
...  

Author(s):  
Se Hun Min ◽  
Jeonghyun Park ◽  
Hyun Kyu Suh

The objective of this study is to investigate the effect of water injection into intake port on the performance of small CI engine. The ECFM-3Z model was applied for the combustion analysis model, and the amount of injected water were varied 10%, 20% and 30% of injected fuel mass. The results of this work were compared in terms of cylinder pressure, rate of heat release (ROHR), and the ISNO and soot emissions. It was found that the cylinder pressure was decreased from 1.2% to 9.2% when the amount of injected water was increased from 10% to 30%. In the results, NO emission significantly decreased from about 24% to about 85% when the amount of injected water increased due to the specific heat and latent heat of water. Considering the test results, the best conditions for the simultaneous reduction of NO and soot is the BTDC 05deg of injection timing and 30% of water injection mass. It can be expected the best IMEP and ISFC characteristics.


Author(s):  
Jim S. Cowart ◽  
Leonard J. Hamilton

A Cooperative Fuels Research (CFR) gasoline engine has been modified to run on computer controlled Port Fuel Injection (PFI) and electronic ignition. Additionally a fast acting sampling valve (controlled by the engine control computer) has been placed in the engine’s intake system between the fuel injector and cylinder head in order to measure the fuel components that are vaporizing in the intake port immediately after the fuel injection event, and separately during the intake valve open period. This is accomplished by fast sampling a small portion of the intake port gases during a specified portion of the engine cycle which are then analyzed with a gas chromatograph. Experimental mixture preparation results as a function of inlet port temperature and pressure are presented. As the inlet port operates at higher temperatures and lower manifold pressures more of the injected fuels’ heavier components evolve into the vapor form immediately after fuel injection. The post-fuel injection fuel-air equivalence ratio in the intake port is characterized. The role of the fuel injection event is to produce from 1/4 to slightly over 1/2 of the combustible fuel-air mixture needed by the engine, as a function of port temperature. Fuel vapor sampling during the intake valve open period suggests that very little fuel is vaporizing from the intake port puddle below the fuel injector. In-cylinder fuel vapor sampling shows that significant fuel vapor generation must occur in the lower intake port and intake valve region.


2016 ◽  
Vol 138 (4) ◽  
Author(s):  
Ahmed O. Said ◽  
Ahmed E. E. Khalil ◽  
Ashwani K. Gupta

Colorless distributed combustion (CDC) has shown to provide ultra-low emissions of NO, CO, unburned hydrocarbons, and soot, with stable combustion without using any flame stabilizer. The benefits of CDC also include uniform thermal field in the entire combustion space and low combustion noise. One of the critical aspects in distributed combustion is fuel mixture preparation prior to mixture ignition. In an effort to improve fuel mixing and distribution, several schemes have been explored that includes premixed, nonpremixed, and partially premixed. In this paper, the effect of dual-location fuel injection is examined as opposed to single fuel injection into the combustor. Fuel distribution between different injection points was varied with the focus on reaction distribution and pollutants emission. The investigations were performed at different equivalence ratios (0.6–0.8), and the fuel distribution in each case was varied while maintaining constant overall thermal load. The results obtained with multi-injection of fuel using a model combustor showed lower emissions as compared to single injection of fuel using methane as the fuel under favorable fuel distribution condition. The NO emission from double injection as compared to single injection showed a reduction of 28%, 24%, and 13% at equivalence ratio of 0.6, 0.7, and 0.8, respectively. This is attributed to enhanced mixture preparation prior to the mixture ignition. OH* chemiluminescence intensity distribution within the combustor showed that under favorable fuel injection condition, the reaction zone shifted downstream, allowing for longer fuel mixing time prior to ignition. This longer mixing time resulted in better mixture preparation and lower emissions. The OH* chemiluminescence signals also revealed enhanced OH* distribution with fuel introduced through two injectors.


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