A Numerical Analysis of the Effect of Mixture Heterogeneity on Combustion in a Premixed Charge Compression Ignition Engine(HCCI, Combustion Processes I)

2004 ◽  
Vol 2004.6 (0) ◽  
pp. 239-246 ◽  
Author(s):  
Katsuya Saijyo ◽  
Takafumi Kojima ◽  
Kazuie Nishiwaki
Keyword(s):  
Numerical Analysis ◽  
Compression Ignition ◽  
Compression Ignition Engine ◽  
Hcci Combustion ◽  
Combustion Processes

Characterizing the cyclic variability of ignition timing in a homogeneous charge compression ignition engine fuelled with n-heptane/iso-octane blend fuels

2008 ◽  
Vol 9 (5) ◽  
pp. 361-397 ◽  
Author(s):  
M Shahbakhti ◽  
C R Koch
Keyword(s):  
Equivalence Ratio ◽  
Homogeneous Charge Compression Ignition ◽  
Coolant Temperature ◽  
Cyclic Variation ◽  
Compression Ignition ◽  
Ignition Timing ◽  
Compression Ignition Engine ◽  
Hcci Combustion ◽  
Cyclic Variations ◽  
Homogeneous Charge

The cyclic variations of homogeneous charge compression ignition (HCCI) ignition timing is studied for a range of charge properties by varying the equivalence ratio, intake temperature, intake pressure, exhaust gas recirculation (EGR) rate, engine speed, and coolant temperature. Characterization of cyclic variations of ignition timing in HCCI at over 430 operating points on two single-cylinder engines for five different blends of primary reference fuel (PRF), (iso-octane and n-heptane) is performed. Three distinct patterns of cyclic variation for the start of combustion (SOC), combustion peak pressure ( Pmax), and indicated mean effective pressure (i.m.e.p.) are observed. These patterns are normal cyclic variations, periodic cyclic variations, and cyclic variations with weak/misfired ignitions. Results also show that the position of SOC plays an important role in cyclic variations of HCCI combustion with less variation observed when SOC occurs immediately after top dead centre (TDC). Higher levels of cyclic variations are observed in the main (second) stage of HCCI combustion compared with that of the first stage for the PRF fuels studied. The sensitivity of SOC to different charge properties varies. Cyclic variation of SOC increases with an increase in the EGR rate, but it decreases with an increase in equivalence ratio, intake temperature, and coolant temperature.

Numerical and experimental study of the combustion phenomenon when the compression ignition is fuelled with mineral diesel

2019 ◽  
Vol 16 (3) ◽  
pp. 341-350 ◽  
Author(s):  
Hariram Venkatesan ◽  
Godwin John J. ◽  
Seralathan Sivamani ◽  
Micha Premkumar T.
Keyword(s):  
Numerical Analysis ◽  
Combustion Characteristics ◽  
Combustion Model ◽  
Transfer Model ◽  
Compression Ignition ◽  
Compression Ignition Engine ◽  
Matlab Simulink ◽  
Content Type ◽  
Combustion Duration ◽  
Dynamic Combustion

Purpose The purpose this experimentation is to study the combustion characteristics of compression ignition engine fuelled with mineral diesel. The reason behind the numerical simulation is to validate the experimental results of the combustion characteristics. Design/methodology/approach The numerical analysis was carried out in this study using MATLAB Simulink, and the zero dimensional combustion model was applied to predict the combustion parameters such as in cylinder pressure, pressure rise rate and rate of heat release. Findings Incorporating the dynamic combustion duration with respect to variable engine load in the zero dimensional combustion model using MATLAB Simulink reduced the variation of experimental and numerical outputs between 5.5 and 6 per cent in this analysis. Research limitations/implications Validation of the experimental analysis is very limited. Investigations were performed using zero dimensional combustion model, which is the very appropriate for analysing the combustion characteristics. Originality/value Existing studies assumed that the combustion duration period as invariant in their numerical analysis, but with the real time scenario occurring in CI engine, that is not the case. In this analysis, mass fraction burnt considering the dynamic combustion duration was incorporated in the heat transfer model to reduce the error variation between experimental and numerical studies.

A Framework of Control-Oriented Reaction-Based Model for Trajectory-Based HCCI Combustion With Variable Fuels

2017 ◽  
Author(s):  
Chen Zhang ◽  
Zongxuan Sun
Keyword(s):  
High Fidelity ◽  
Compression Ignition ◽  
Combustion Control ◽  
Free Piston ◽  
Hcci Combustion ◽  
Least Squares Optimization ◽  
Pure Compression ◽  
Reduce Emissions ◽  
Combustion Processes ◽  
Engine Cycle

A novel combustion control, i.e. the trajectory-based combustion control, was proposed previously. This control is enabled by free piston engines (FPEs) and utilizes the FPE’s controllable piston trajectory to enhance thermal efficiency, reduce emissions and realize variable fuels applications. On top of that, a control-oriented model was also developed aimed to implement the trajectory-based combustion control in real-time. Specifically, a unique phase separation method was proposed in the model, which separates an engine cycle into four phases (pure compression, ignition, heat release and pure expansion) and employs the minimal reaction mechanism accordingly. In this paper, the framework of the previous control-oriented model is extended to variable fuels, such as methane, n-heptane and bio-diesel. Such an extension is reasonable since the separated four phases are representative in typical combustion processes of all fuels within an engine cycle. Besides, a least-squares optimization is formulated to calibrate the chemical kinetics variables for each fuel. At last, simulation results and the related analysis show that all the derived control-oriented models have high fidelity and much lighter computational burdens to represent the HCCI combustion of each fuel along variable piston trajectories.

Effect of Premixed Diesel Fuel on Partial HCCI Combustion Characteristics

2014 ◽  
Vol 663 ◽  
pp. 26-33
Author(s):  
Y.H. Teoh ◽  
H.H. Masjuki ◽  
M.A. Kalam ◽  
Muhammad Afifi Amalina ◽  
H.G. How
Keyword(s):  
Diesel Fuel ◽  
Engine Speed ◽  
Direct Injection ◽  
Compression Ignition ◽  
Cylinder Pressure ◽  
Compression Ignition Engine ◽  
Hcci Combustion ◽  
Light Duty ◽  
Auto Ignition ◽  
Ignition Characteristics

This study investigated the effects of premixed diesel fuel on the auto-ignition characteristics in a light duty compression ignition engine. A partial homogeneous chargecompression ignition (HCCI) engine was modified from a single cylinder, four-stroke, direct injection compression ignition engine. The partial HCCI is achieved by injecting diesel fuel into the intake port of the engine, while maintaining diesel fuel injected in cylinder for combustion triggering. The auto-ignition of diesel fuel has been studied at various premixed ratios from 0 to 0.60, under engine speed of 1600 rpm and 20Nm load. The results for performance, emissions and combustion were compared with those achieved without premixed fuel. From the heat release rate (HRR) profile which was calculated from in-cylinder pressure, it is clearly observed that two-stage and three-stage ignition were occurred in some of the cases. Besides, the increases of premixed ratio to some extent have significantly reduced in NO emission.

Sign in / Sign up

Export Citation Format

Share Document