Showing papers on "Homogeneous charge compression ignition published in 2018"
TL;DR: In this paper, a literature review has been made about pre-chamber ignition systems as lean combustion technology, focusing in the several investigations regarding combustion and emissions characteristics and presenting the key advantages and challenges in pre chamber ignition technology application.
144 citations
TL;DR: In this article, the effect of different injection strategies (single and two pulses injection of pilot diesel fuel) on the combustion performance and emissions of a heavy duty natural gas/diesel dual-fuel engine at 25% engine load was evaluated.
100 citations
TL;DR: In this article, the rate constants for five reaction classes about the model molecule PODE1, including hydrogen abstraction, beta-scission of corresponding R radicals, isomerization of RO2 radicals, and decomposition of QOOH radicals, were calculated with canonical transition state theory at the CCSD(T)-F12a/aug-cc-pVTZ//M06-2X/def2-TZVPP or CBS-QB3/B3LYP/CBSB7 level of theory.
99 citations
TL;DR: In this paper, the authors performed a numerical study of nine (9) different alternative bio-fuels and pure diesel and compared the results with the results of pure diesel in a single cylinder, naturally aspirated, water cooled, direct injection diesel engine with different engine load (20, 40, 60, 80% and 100%), constant compression ratio (CR17.5), higher nozzle opening pressure (220 bar) and advance injection timing (23° CA before TDC).
91 citations
TL;DR: In this paper, the authors investigated the effect of hydrogen energy share (HES) enhancement on engine performance and emissions and found that HES is beneficial in reducing harmful emissions at low and mid loads.
89 citations
TL;DR: In this paper, the in-cylinder combustion for low octane 70 primary reference fuel (PRF70) was investigated by the method of the flame index during the transition from homogeneous charge compression ignition (HCCI) combustion to partially premixed combustion (PPC).
71 citations
01 Jan 2018
TL;DR: In this article, an overview of the effects of fuel molecular structure on the combustion and emissions characteristics of compression ignition engines, highlighting in particular the submolecular features common to a variety of potential fuels.
Abstract: Future fuels for compression ignition engines will be required both to reduce the anthropogenic carbon dioxide emissions from fossil sources and to contribute to the reductions in the exhaust levels of pollutants, such as nitrogen oxides and particulate matter. Via various processes of biological, chemical and physical conversion, feedstocks such as lignocellulosic biomass and photosynthetic micro-organisms will yield a wide variety of potential fuel molecules. Furthermore, modification of the production processes may allow the targeted manufacture of fuels of specific molecular structure. This paper therefore presents an overview of the effects of fuel molecular structure on the combustion and emissions characteristics of compression ignition engines, highlighting in particular the submolecular features common to a variety of potential fuels. An increase in the straight-chain length of the alkyl moiety reduces the duration of ignition delay, and the introduction of double bonds or branching to an alkyl moiety both increase ignition delay. The movement of a double bond towards the centre of an alkyl chain, or the addition of oxygen to a molecule, can both increase and decrease the duration of ignition delay dependent on the overall fuel structure. Nitrogen oxide emissions are primarily influenced by the duration of fuel ignition delay, but in the case of hydrogen and methane pilot-ignited premixed combustion arise only at flame temperatures sufficiently high for thermal production. An increase in aromatic ring number and physical properties such as the fuel boiling point increase particulate matter emissions at constant combustion phasing.
63 citations
TL;DR: In this article, a single cylinder, four stroke, direct injection, vertical, water cooled, variable compression ratio, multi fuel engine was used to operate in dual fuel mode and the results were evaluated and compared on the basis of combustion, performance and emission parameters.
61 citations
TL;DR: In this paper, the effects of global equivalence ratio ( ϕ global ) and initial charge temperature, which were controlled by means of intake throttling, charge heating, and exhaust gas recirculation (EGR) strategies, were investigated to overcome the bulk quenching phenomenon under low load conditions of DF-PCCI operation in a heavy-duty (HD) single cylinder engine.
59 citations
TL;DR: The sensitivity analysis proved that bowl depth, bowl diameter, toroidal radius, and throat diameter played a vital role in the fuel consumption parameter and emission characteristics even at the manufacturing tolerance variations.
Abstract: A numerical study was carried out to study the effect of various combustion bowl parameters on the performance behavior, combustion characteristics, and emission magnitude on a single cylinder diesel engine. A base combustion bowl and 11 different combustion bowls were created by varying the aspect ratio, reentrancy ratio, and bore to bowl ratio. The study was carried out at engine rated speed and a full throttle performance condition, without altering the compression ratio. The results revealed that the combustion bowl parameters could have a huge impact on the performance behavior, combustion characteristics, and emission magnitude of the engine. The bowl parameters, namely throat diameter and toroidal radius, played a crucial role in determining the performance behavior of the combustion bowls. It was observed that the combustion bowl parameters, namely central pip distance, throat diameter, and bowl depth, also could have an impact on the combustion characteristics. And throat diameter and toroidal radius, central pip distance, and toroidal corner radius could have a consequent effect on the emission magnitude of the engine. Of the different combustion bowls tested, combustion bowl 4 was preferable to others owing to the superior performance of 3% of higher indicated mean effective pressure and lower fuel consumption. Interestingly, trade-off for NO
x
emission was higher only by 2.85% compared with the base bowl. The sensitivity analysis proved that bowl depth, bowl diameter, toroidal radius, and throat diameter played a vital role in the fuel consumption parameter and emission characteristics even at the manufacturing tolerance variations.
59 citations
TL;DR: In this paper, an internal combustion engine is used as a reactor for partial oxidation to produce syngas together with mechanical work, and experiments were performed in a single-cylinder engine operated on methane/air.
TL;DR: In this article, a homogeneous charge compression ignition (HCCI) combustion engine was evaluated using alcohol-gasoline fuel blends and two-stage direct injection (TSDI) strategy, where the first injection timing was fixed in intake stroke and the second injection timing close to the compression top dead center (TDC).
TL;DR: In this paper, the in-cylinder combustion visualization and engine-out soot particle emissions were investigated in an optical diesel engine fueled with low octane gasoline, and a single injection strategy with an early injection timing (−30 CAD aTDC) was employed to achieve partially premixed combustion (PPC) condition.
TL;DR: In this paper, the ringing intensity (RI) of a hydrogen-HCCI engine was investigated using chemical kinetics and artificial neural network (ANN) for HCCI operation.
TL;DR: In this article, the authors compared three different low temperature combustion (LTC) strategies, viz. Homogenous Charge Compression Ignition (HCCI), PCCI, and Reactivity Controlled CompressionIgnition (RCCI) to achieve lower emissions and wider operating range.
TL;DR: In this paper, an experimental investigation is conducted to study GCI knocking characteristics, which shows an increasing trend of both brake mean effective pressure (BMEP) and knock intensity as injection timing advances.
TL;DR: In this paper, the effect of physical properties on combustion homogeneity when moving from homogenized charge compression ignition (HCCI) to compression ignition combustion is studied, and it is shown that combustion is more stratified for dieseline whereas it is premixed for naphtha and PRF60.
TL;DR: In this article, a four-stroke single-cylinder gasoline engine has been modified to allow CAI combustion by means of adapted valve trains enabling to keep hot residual gases inside the cylinder, which will provoke the fuel autoignition.
TL;DR: In this paper, advanced combustion control strategies have been experimentally investigated to improve ethanol-diesel dual-fuel operation at a high engine load of 1.8 MPa net indicated mean effective pressure.
TL;DR: In this paper, a skeletal oxidation mechanism composed of 47 species and 177 reactions was developed for n-pentanol based on the decoupling methodology in a homogeneous charge compression ignition engine in coupling with a three-dimensional CFD model.
TL;DR: In this article, an experimentally developed multi-mode LTC-SI engine is integrated into a parallel hybrid electric configuration, where the engine operation modes include homogeneous charge compression ignition (HCCI), reactivity controlled compression ignition, and conventional SI.
TL;DR: In this article, the dynamics of low-temperature ignition of n-hexane/air mixtures, and identifies chemical pathways that characterize the combustion process, were explored using tools generated from the computational singular perturbation (CSP) approach to two distinct ignition phenomena: constant volume and compression ignition.
TL;DR: This article presents an original technical solution, which enables to regulate the whole self-ignition process and in this way to ensure a reliable operation of the HCCI engine.
TL;DR: In this paper, four different chemical kinetic mechanisms for two butanol isomers (n-butanol and isobutanol) in a single-zone engine model and compares the results to experiments conducted on a Homogeneous Charge Compression Ignition (HCCI) engine.
TL;DR: In this article, the effects of concentration stratification and reactivity stratification on combustion and emission characteristics were investigated in a single-cylinder diesel engine and different concentration stratifications were designed by five port injection ratios.
TL;DR: In this paper, the effects of a coupling strategy, which combines internal/external exhaust gas recirculation (i & e-EGR) and split injection, on knock suppression in SACI mode were investigated in a high-compression-ratio, single-cylinder gasoline engine with a fully variable valve system.
TL;DR: In this paper, an experimental study on the operation of an internal combustion engine fuelled by SOFC anode off-gas was conducted, where the homogeneous charge compression ignition (HCCI) method was selected instead of spark ignition as the combustion strategy of the engine in the hybrid system.
TL;DR: In this article, the effects of a glow plug on the gas temperature distribution prior to ignition in HCCI combustion are investigated, and two custom sleeve adapters were constructed to allow the glow plug access to the gasoline engine in two different locations.
TL;DR: In this paper, a laser ignition of lean CNG-air mixtures is experimentally investigated at different compression ratios and air-fuel ratios, in order to extract full potential of CNG for transport applications.
TL;DR: In this article, a 2D CFD simulation of an HCCI engine operating on iso-octane based fuel blends comprising hydrogen or syngas as additives is conducted on the basis of two values of fuel-to-air equivalence ratio ϕ = 0.4 and 0.2.