Spectroscopic Investigation of the Combustion Process in DME Compression Ignition Engine

Author(s):  
Mitsuharu Oguma ◽  
Gisoo Hyun ◽  
Shinichi Goto ◽  
Mitsuru Konno ◽  
Kazuya Oyama
2018 ◽  
Vol 184 ◽  
pp. 01013
Author(s):  
Corneliu Cofaru ◽  
Mihaela Virginia Popescu

The paper presents the research designed to develop a HCCI (Homogenous Charge Compression Ignition) engine starting from a spark ignition engine platform. The chosen test engine was a single cylinder, four strokes provided with a carburettor. The results of experimental research data obtained on this version were used as a baseline for the next phase of the research. In order to obtain the HCCI configuration, the engine was modified, as follows: the compression ratio was increased from 9.7 to 11.5 to ensure that the air – fuel mixture auto-ignite and to improve the engine efficiency; the carburettor was replaced by a direct fuel injection system in order to control precisely the fuel mass per cycle taking into account the measured intake air-mass; the valves shape were modified to provide a safety engine operation by ensuring the provision of sufficient clearance beetween the valve and the piston; the exchange gas system was changed from fixed timing to variable valve timing to have the possibilities of modification of quantities of trapped burnt gases. The cylinder processes were simulated on virtual model. The experimental research works were focused on determining the parameters which control the combustion timing of HCCI engine to obtain the best energetic and ecologic parameters.


2005 ◽  
Vol 6 (5) ◽  
pp. 487-495 ◽  
Author(s):  
K Saijyo ◽  
T Kojima ◽  
K Nishiwaki

We analyzed the interrelationships between mixture heterogeneity and reaction in a premixed charge compression ignition (PCCI) combustion, using large eddy simulation (LES) in conjunction with a reaction kinetics model. The aim of this analysis is to find the statistical characteristics of the mixture heterogeneity in a turbulent flowfield for moderating the PCCI combustion and for increasing an output limit, which is restricted by a severe knock. Several different initial conditions of heterogeneity of an air-fuel or air-fuel-EGR gas mixture were given at the intake valve closing time by a new method, which generated statistically reasonable turbulent fluctuations in both velocity and fuel mass fraction fields. The autoignition and combustion behaviours were analysed for several different sets of the r.m.s. and the length scale of the fluctuations in the fuel mass fraction. The analyses show that the combination of a larger r.m.s. value and a longer-length scale of the fluctuations in fuel mass fraction is effective to slow the combustion in a hot flame reaction phase and to avoid knocking. The analytical results also show that the heterogeneous distribution of an EGR gas has a considerable effect in making the combustion slower, even when a fuel-air mixture is homogeneous.


1938 ◽  
Vol 138 (1) ◽  
pp. 415-493 ◽  
Author(s):  
J. W. Drinkwater ◽  
A. C. Egerton

The object of the work, which was carried out in the University Engineering Laboratory, Oxford, was to investigate the combustion process in a compression-ignition engine by determining the extent of the chemical reactions of the fuel and air at various stages during the compression and expansion strokes. The results of the tests are illustrated by several curves showing the percentage volumes of the constituent gases in the engine cylinder at different points in the cycle. Various inferences are drawn concerning the combustion in this type of engine. Attempts were made to determine the concentration of aldehydes in the gases, but the tests showed that the amount was less than anticipated. Oxides of nitrogen were detected, and considered to have an influence upon cylinder wall corrosion. It is suggested that there is scope for further work using the sampling method for investigating combustion problems in engines under running conditions.


CFD letters ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 1-11
Author(s):  
Fatin Farhanah Zulkurnai ◽  
Wan Mohd Faizal Wan Mahmood ◽  
Norhidayah Mat Taib ◽  
Mohd Radzi Abu Mansor

Reactivity controlled compression ignition (RCCI) engine give advantages over conventional diesel engine with the promising engine power and good control on NOx and soot emission. The trend of the RCCI concept is still new and Is very important to control the ignition in order to control the combustion progress and emission. The objective of this study is to provide data on the combustion characteristics and emission of diesel as high reactive, and ethanol as the low reactive fuel in the RCCI engine. The engine speed and injection timing were varied. Simulation work was conducted by using the Converge CFD software based on the Yanmar TF90 diesel engine parameter. Results show that operating the engine at low speed resulting in better engine performance and low carbon emissions due to the sufficient oxygen contents. For the high-speed engine, advancing the injection timing improves the fuel and air reactivity and steeper the equivalence ratio gradient, which result in a complete combustion process.


2015 ◽  
Vol 162 (3) ◽  
pp. 91-101
Author(s):  
Sławomir WIERZBICKI ◽  
Maciej MIKULSKI ◽  
Michał ŚMIEJA

Seeking alternative sources of energy for its more effective use, reducing emissions of toxic pollutants to the atmosphere and counteracting global warming are nowadays the major areas of development in the power industry, including the design of combustion engines. Currently, the research into the use of new fuels, which may be effective sources of energy, is performed by many scientific centres. The use of biogas for production of energy in cogeneration systems is one of the ways for improvement of energy balance. In the research described herein, a dual-fuel compression ignition engine was fuelled with gaseous fuel with variable CNG and CO2 ratios. The tests were performed for engine fuelling controlled by both an original controller with the software optimised for single-fuel operation and for the injection of a pilot dose of diesel controlled by a dedicated controller enabling the adjustment and control of the injection and dose parameters. This paper presents the effect of carbon dioxide content in gaseous fuel on the combustion process and emission of toxic compounds in the engine examined.


2019 ◽  
Vol 141 (5) ◽  
Author(s):  
Xiao Huang ◽  
Lulu Kang ◽  
Mateos Kassa ◽  
Carrie Hall

In-cylinder pressure is a critical metric that is used to characterize the combustion process of engines. While this variable is measured on many laboratory test beds, in-cylinder pressure transducers are not common on production engines. As such, accurate methods of predicting the cylinder pressure have been developed both for modeling and control efforts. This work examines a cylinder-specific pressure model for a dual fuel compression ignition engine. This model links the key engine input variables to the critical engine outputs including indicated mean effective pressure (IMEP) and peak pressure. To identify the specific impact of each operating parameter on the pressure trace, a surrogate model was produced based on a functional Gaussian process (GP) regression approach. The pressure trace is modeled as a function of the operating parameters, and a two-stage estimation procedure is introduced to overcome various computational challenges. This modeling method is compared to a commercial dual fuel combustion model and shown to be more accurate and less computationally intensive.


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