homogeneous charge compression ignition (hcci) combustion is a pioneer method of combustion in which pre-mixed fuel and oxidizer (typically air) are compressed to the point of auto-ignition. hcci engines can operate with most alternative fuels, especially, dimethyl ether (dme) which has been tested as a possible diesel fuel due to its simultaneously low nox and pm emissions. in this paper a sin...

The parameters that are present in Exhaust Gas Recirculation (EGR) are believed to provide an important contribution to control the auto-ignition process of the Homogeneous Charge Compression Ignition (HCCI) in an engine. For the investigation of the behaviour of the autoignition process, a kinetic multi-component mechanism has been developed in former work, containing 62 reactions and 49 speci...

The Homogeneous Charge Compression Ignition (HCCI) combustion concept lacks direct ignition timing control, instead the auto ignition depends on the operating condition. Since auto ignition of a homogeneous mixture is very sensitive to operating conditions, a fast combustion timing control is necessary for reliable operation. Hence, feedback is needed and the crank angle of 50% burnt (CA50) has...

In this study, the effect of second injection timing on the combustion and emissions characteristics of a direct injection HCCI gasoline engine was investigated by using ethanol and methanol blended gasoline fuel. For this aim, a diesel engine was converted to an electronically controlled HCCI gasoline engine. The injection timings and fuel quantity for each injection were adjusted to get desir...

We present a computational tool to develop an exhaust gas recirculation (EGR) – air-fuel ratio (AFR) operating range for homogeneous charge compression ignition (HCCI) engines. A single cylinder Ricardo E-6 engine running in HCCI mode, with external EGR is simulated using an improved probability density function (PDF) based engine cycle model. For a base case, the incylinder temperature and unb...

A new type of high chromium cast iron (HCCI) was prepared, and its microstructure, mechanical properties, abrasion resistance were investigated systematically. Results showed that after surface carburizing chromizing, the microstructure HCCI mainly consists martensite, boride (M2B), carbide (M7C3), accompanied with a large amount secondary precipitations M23C6. Moreover, morphology hardness in ...

To acquire a high amount of information of the behaviour of the Homogeneous Charge Compression Ignition (HCCI) auto-ignition process, a reduced surrogate mechanism has been composed out of reduced n-heptane, iso-octane and toluene mechanisms, containing 62 reactions and 49 species. This mechanism has been validated numerically in a 0D HCCI engine code against more detailed mechanisms (inlet tem...

Premixed or partially premixed compression ignition modes, such as homogeneous charge compression ignition (HCCI), have been a particular focus among researchers because of their potential to deliver enhanced fuel efficiency and meet exhaust emissions mandates without the addition of costly after-treatment technologies as currently required with traditional spark ignition (SI) and direct inject...

Homogeneous charge compression ignition (HCCI) is a novel combustion strategy for IC engines that exhibits dramatic decreases in fuel consumption and exhaust emissions. Originally conceived in 1979, the HCCI methodology has been revisited several times by industry but has yet to be implemented because the process is difficult to control. To help address these control challenges, the authors her...