Control of homogeneous charge compression ignition combustion in a two-cylinder gasoline direct injection engine with negative valve overlap

2007 ◽  
Vol 1 (3) ◽  
pp. 311-315
Author(s):  
Zhi Wang ◽  
Jianxin Wang ◽  
Shijin Shuai ◽  
Qingjun Ma ◽  
Guohong Tian
Keyword(s):  
Homogeneous Charge Compression Ignition ◽  
Direct Injection ◽  
Gasoline Direct Injection ◽  
Compression Ignition ◽  
Direct Injection Engine ◽  
Gasoline Direct Injection Engine ◽  
Negative Valve Overlap ◽  
Compression Ignition Combustion ◽  
Valve Overlap ◽  
Homogeneous Charge

Control of a spark ignition homogeneous charge compression ignition mode transition on a gasoline direct injection engine

2007 ◽  
Vol 221 (7) ◽  
pp. 867-875 ◽  
Author(s):  
G Tian ◽  
Z Wang ◽  
Q Ge ◽  
J Wang ◽  
S Shuai
Keyword(s):  
Homogeneous Charge Compression Ignition ◽  
Direct Injection ◽  
Spark Ignition ◽  
Gasoline Direct Injection ◽  
Compression Ignition ◽  
Combustion Mode ◽  
Key Issues ◽  
Cam Profile ◽  
Negative Valve Overlap ◽  
Homogeneous Charge

The hybrid combustion mode is an ideal operation strategy for a gasoline homogeneous charge compression ignition (HCCI) engine. A stable and smooth spark ignition (SI)/HCCI switch has been an issue in the research on multimode combustion. In this paper, the switch process has two key issues; the cam profile and throttle opening. With the developed two-stage cam system, the valve phase strategy can be switched within one engine cycle, from the normal cam profile for the SI mode to a negative valve overlap (NVO) profile for the HCCI mode, or vice versa. For a smoother and more stable switch, the throttle change was separated from the cam profile switch, which was called the stepped switch. The effect of throttle opening on HCCI combustion was studied, and the results showed that the concept of the stepped switch was reliable. With gasoline direct injection (GDI) the combustion mode switches from both SI and HCCI sides were smooth, rapid, and robust, without any abnormal combustion such as knocking and misfiring.

scholarly journals Cycle-by-cycle variations in autonomous and spark assisted homogeneous charge compression ignition combustion of stoichiometric air–fuel mixture

2018 ◽  
Vol 10 (3) ◽  
pp. 231-243 ◽  
Author(s):  
Jacek Hunicz
Keyword(s):  
Homogeneous Charge Compression Ignition ◽  
Fuel Injection ◽  
Fuel Mixture ◽  
Compression Ignition ◽  
Indicated Mean Effective Pressure ◽  
Start Of Injection ◽  
Negative Valve Overlap ◽  
Compression Ignition Combustion ◽  
Valve Overlap ◽  
Homogeneous Charge

This study investigates cycle-by-cycle variations in a gasoline fuelled, homogeneous charge compression ignition (HCCI) engine with internal exhaust gas recirculation. In order to study the effects of exhaust-fuel reactions occurring prior to the main combustion event fuel was injected directly into the cylinder at two selected timings during the negative valve overlap period. The engine was operated as both autonomous HCCI and spark assisted HCCI (SA-HCCI). The primary interest in this work was the operating region where the engine is switched between HCCI and spark ignition modes, thus operation with stoichiometric air–fuel mixture, which is typical for this region, was considered. Cycle-by-cycle variations in both combustion timing and indicated mean effective pressure (IMEP) were investigated. It was found that long-period oscillations of the IMEP occur when fuel injection is started at early stages of the negative valve overlap period, and that these can be suppressed by delaying the start of injection. This behaviour remained even when fuel injection was split into early and late-negative valve overlap injections. Spark assisted operation allowed eliminating late combustion cycles, thus improving thermal efficiency. However, characteristic patterns of IMEP variations were found to be the same for both HCCI and SA-HCCI operations, irrespective of the adopted negative valve overlap fuel injection strategy, as evidenced by using symbol-sequence statistics.

scholarly journals A thermodynamic model for homogeneous charge compression ignition combustion with recompression valve events and direct injection: Part I — Adiabatic core ignition model

2016 ◽  
Vol 18 (7) ◽  
pp. 657-676 ◽  
Author(s):  
Prasad S Shingne ◽  
Robert J Middleton ◽  
Dennis N Assanis ◽  
Claus Borgnakke ◽  
Jason B Martz
Keyword(s):  
Fluid Dynamics ◽  
Computational Fluid Dynamics ◽  
Homogeneous Charge Compression Ignition ◽  
Direct Injection ◽  
Operating Conditions ◽  
Compression Ignition ◽  
Auto Ignition ◽  
Dynamics Simulations ◽  
Compression Ignition Combustion ◽  
Homogeneous Charge

This two-part article presents a model for boosted and moderately stratified homogeneous charge compression ignition combustion for use in thermodynamic engine cycle simulations. The model consists of two components: one an ignition model for the prediction of auto-ignition onset and the other an empirical combustion rate model. This article focuses on the development and validation of the homogeneous charge compression ignition model for use under a broad range of operating conditions. Using computational fluid dynamics simulations of the negative valve overlap valve events typical of homogeneous charge compression ignition operation, it is shown that there is no noticeable reaction progress from low-temperature heat release, and that ignition is within the high-temperature regime ( T > 1000 K), starting within the highest temperature cells of the computational fluid dynamics domain. Additional parametric sweeps from the computational fluid dynamics simulations, including sweeps of speed, load, intake manifold pressures and temperature, dilution level and valve and direct injection timings, showed that the assumption of a homogeneous charge (equivalence ratio and residuals) is appropriate for ignition modelling under the conditions studied, considering the strong sensitivity of ignition timing to temperature and its weak compositional dependence. Use of the adiabatic core temperature predicted from the adiabatic core model resulted in temperatures within ±1% of the peak temperatures of the computational fluid dynamics domain near the time of ignition. Thus, the adiabatic core temperature can be used within an auto-ignition integral as a simple and effective method for estimating the onset of homogeneous charge compression ignition auto-ignition. The ignition model is then validated with an experimental 92.6 anti-knock index gasoline-fuelled homogeneous charge compression ignition dataset consisting of 290 data points covering a wide range of operating conditions. The tuned ignition model predictions of [Formula: see text] have a root mean square error of 1.7° crank angle and R2 = 0.63 compared to the experiments.

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