Publications Scientifiques
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Item Investigationof pilot injection strategy effect on performance and emissions ofdual-fuel engine(Toronto Metropolitan University, 2023) Ouchikh, Sarah; Lounici, Mohand Said; Loubar, Khaled; Tazerout, MohandThe dual-fuel combustion is a promising technique for methane utilization in internal combustion. This mode has the potential to reduce emissions of nitrogen oxides and particulate matter. However, this mode presents some deficits at low loads, especially concerning unburned hydrocarbons and carbon monoxide emissions. In the current study, experimental research was conducted to investigate the effect of diesel injection strategy, including single and split injections, on the performance and emissions of a methane/diesel dual-fuel engine.Item Development of knock prediction technique in dual fuel engines and its mitigation with direct water injection(Elsevier, 2024) Sehili, Youcef; Loubar, Khaled; Lounici, Mohand Said; Tarabet, Lyes; Cerdoun, Mahfoudh; Lacroix, ClémentIn the face of increasing emission restrictions and the parsimony of conventional fuels, dual fuel engine is presented as a promising solution that is satisfactory for environmental and economic aspects. However, this type of engine is limited by certain problems such as knocking, which negatively influences overall operation. For this reason and for optimal engine operation, prediction of this undesirable auto-ignition is essential. The approach developed in this work for this purpose, is based on dividing the combustion chamber into two zones to follow the thermodynamic properties of the unburnt gases where knock may occur. This thermodynamic modeling is coupled with a model based on Arrhenius equation for the auto-ignition delay as a function of crank angle. In addition, in order to make the model more predictive with the minimum of parameters to be calibrated experimentally, an analysis of variables is used for different engine conditions. The selected parameters undergo a correction before being modeled according to response surfaces methodology. After validation of the model using experimental results, it is coupled with a CFD calculation model to develop a global approach aimed at preventing knocking during dual fuel mode. The model makes it possible to predict knock onset with good precision. Consequently, preventing this phenomenon is possible. Water injection technique is therefore used for this objective. Accurate prediction was useful for knock avoidance via water injection strategy. Our results confirmed the effectiveness of this technique, justified mainly by water injection characteristics. The precision of the instant of knocking predicted by the developed model implied an optimal instant for water injection. Overall, this global model can be considered as a valuable means for knock prediction and prevention in dual fuel mode.Item Investigation of natural gas enrichment with high hydrogen participation in dual fuel diesel engine(Elsevier, 2021) Benbellil, Messaoud Abdelalli; Lounici, Mohand Said; Loubar, Khaled; Tazerout, MohandThis study explores the impact of natural gas (NG) enrichment with high H2 concentrations (20, 30, 40 and 50 by v %) on combustion characteristics, engine performance, exhaust emissions and knock in a compression ignition engine running in dual fuel (DF) mode. Results indicated that H2 addition to NG contributes to enhance gaseous fuel combustion that corresponds to an increased heat release rate (HRR) during the premixed phase of gaseous fuel that also causes an increase in the pressure peak, particularly at high loads. The maximum pressure peak and HRR correspond to 50% H2 addition. The combustion duration is shortened for all H2 mixtures. Regarding engine performance, an important benefit in terms of brake thermal efficiency is noted for all H2 blends; it increases with increasing enrichment rate and reaches approximately 16% increase for the 50% H2 mixture relative to pure NG case. Moreover, enriching NG with H2 is an effective solution for reducing unburned hydrocarbons and carbon monoxide at moderate to high engine loads. However, for NOx emissions, the addition of H2 to NG is only attractive at low and moderate loads. In addition, over 80% engine load, NG enrichment with H2 generates knock, which rapidly reaches high intensities.Item Investigation of natural gas enrichment with high hydrogen participation on knock in dual fuel diesel engine at high loads(2021) Benbellil, Messaoud Abdelalli; Lounici, Mohand Said; Loubar, Khaled; Tazrout, MohandWith growing worries about the safety of the environment and the lack of supplies of crude oil, a great deal of effort has been made to use alternative fuels in engines. For internal combustion engines, natural gas (NG) is one of the most attractive available fuels. The dual fuel (DF) concept is an effective way for its use. NG has a slow burning velocity and limited lean-burn ability. Enriching NG with hydrogen is an effective way to mitigate such demerits, since H2 is characterized by a rapid combustion speed, wider combustion limit and low ignition energy. For high engine loads operation, the engine risks to go through a hazardous knocking regime. This study explores experimentally the effect of NG enrichment with high H2 concentrations (20, 30, 40 and 50 by v %) in DF mode on knock at high engine loads of a compression ignition engine. Results indicated that enriching NG with high H2 concentrations in DF mode is an interesting technique for improving dual fuel engine up to 80% load without any knock. However, beyond this load (at 90% of full engine load) the knocking phenomenon appears with high intensities and occurs before achieving the maximum output power of the diesel engine (4.5 kW). In the case of pure NG, the engine reach the maximum output power (100% of full engine load) without knocking. An occurrence of knock with H2 addition might be due to a very low methane number of H2 that means hydrogen is highly prone to generate the knock than NG, which is mainly composed of methane. Knocking combustion causes major engine damage, reduces the efficiency and requires particular attention. Therefore, it is advisable to operate DF engine with H2 enrichment at the safe zone (from 20% to 80% engine load) to prevent knock.Item Numerical investigation on combustion characteristics of both diesel and dual fuel engine at part load conditions using converge cfd(2019) Benbellil, Messaoud Abdelalli; Lounici, Mohand Said; Loubar, Khaled; Ouchikh, SarahPetroleum resources are nite and, therefore, search for their alternative non-petroleum fuels for internal combustion engines is continuing all over the world. Moreover, gases emitted by petroleum fuel-driven vehicles harm the environment and human health. Dual-fuel engine (diesel/NG) represents one of a possible solution to reduce emissions from a diesel engine. Therefore, this method has been given a lot of attention from many researchers to improve engine performance and reduce diesel consumption, particularly at full loads. However, it is necessary to study the dual-fuel (DF) combustion process with more details at part loads, due to the poor performance at these conditions. This study numerically investigated the e ect of DF (dual fuel) operating mode on combustion characteristics of an existing diesel engine using natural gas as primary fuel and neat diesel as pilot fuel at part loads by adopting a 3D-CFD simulation using the code CONVERGE. A series of numerical simulations were carried out, the purpose of which to gain a better understanding of the combustion behavior in dual-fuel engines. The results are rst validated using experimental data. A comparison with neat diesel fuel operation is achieved.Item Bio-oil recovery from olive mill wastewater in sub-/supercritical alcohol-water system(Elsevier, 2019) Hadhoum, Loubna; Burnens, Gaëtan; Loubar, Khaled; Balistrou, Mourad; Tazerout, MohandItem Hydrothermal liquefaction of oil mill wastewater for bio-oil production in subcritical conditions(Elsevier, 2016) Hadhoum, Loubna; Balistrou, Mourad; Burnens, Gaëtan; Loubar, Khaled; Tazerout, MohandItem Experimental investigation on NG dual fuel engine improvement by hydrogen enrichment(Elsevier, 2014) Lounici, Mohand Said; Boussadi, Asma; Loubar, Khaled; Tazerout, MohandItem Towards improvement of natural gas-diesel dual fuel mode : an experimental investigation on performance and exhaust emissions(Elsevier, 2014) Lounici, Mohand Said; Loubar, Khaled; Tarabet, Lyes; Balistrou, Mourad; Niculescu, Dan-Catalin; Tazerout, MohandItem Experimental assessment of performance and emissions maps for biodiesel fueled compression ignition engine(Elsevier, 2016) Kezrane, Cheikh; Awad, Sary; Loubar, Khaled; Liazid, Abdelkrim; Tazerout, Mohand