Compression Ignition Research Articles

Comparison between diesel-only mode and methanol/diesel dual-fuel mode on in-cylinder combustion, performance and emissions of common-rail engine based on speed

ABSTRACT Methanol/diesel dual-fuel (DF) mode paves the way for the utilization of methanol in compression ignition engines. This study conducted a comparative investigation of in-cylinder combustion, conventional emissions and unconventional emissions in a common-rail engine operating under diesel-only (DO) mode and DF mode at various speeds. The results show that, compared to DO mode, the DF mode exhibits a longer ignition delay, shorter combustion duration, and a more concentrated heat release in the cylinder. The brake thermal efficiency of DF mode is consistently lower than that of DO mode, with the maximum reduction reaching 6.2% at 2200 r/min. The DF mode simultaneously reduces NOx and soot emissions, with NOx reduced by 16.3% at 2200 r/min and soot reduced by 64.3% at 1600 r/min. However, the DF mode significantly increases NO2, CH3OH and HCHO emissions compared to DO mode, particularly at higher speeds. At 2200 r/min, NO2/NOx ratio reaches a maximum of 84.5%. At 1900 r/min, CH3OH and HCHO emissions of DF mode are 197.3 and 71.2 times higher than those of DO mode, respectively. The DF mode significantly reduces CO2 emissions, with the reduction increasing with speed and peaking at 3.8% at 2200 r/min.

Effect of hydrogen and diethyl ether addition on 5E attributes of compression ignition engine using papaya seed oil-diesel blend

Effect of hydrogen and diethyl ether addition on 5E attributes of compression ignition engine using papaya seed oil-diesel blend

Development of ammonia-biodiesel fueled agricultural tractor: Aspects of retrofitting a compression ignition engine to direct ammonia injection

Development of ammonia-biodiesel fueled agricultural tractor: Aspects of retrofitting a compression ignition engine to direct ammonia injection

Effect of Al2O3 nano-particle on the performance and emission characteristics of millettia ferruginea (Berbera) biodiesel blend fuel on single cylinder compression ignition engine

Effect of Al2O3 nano-particle on the performance and emission characteristics of millettia ferruginea (Berbera) biodiesel blend fuel on single cylinder compression ignition engine

Investigating the combined effects of hydrogen-enriched second-generation biodiesel blends derived from Colza and Margosa oils in dual-fuel compression ignition engine

Investigating the combined effects of hydrogen-enriched second-generation biodiesel blends derived from Colza and Margosa oils in dual-fuel compression ignition engine

Impact of short-chain alcohols on carbonyl emissions in dual-fuel compression ignition engines

Impact of short-chain alcohols on carbonyl emissions in dual-fuel compression ignition engines

Methylcyclohexane as a hydrogen-rich fuel for compression ignition engines: Enhancing combustion efficiency and reducing environmental impact

Methylcyclohexane as a hydrogen-rich fuel for compression ignition engines: Enhancing combustion efficiency and reducing environmental impact

Experimental investigation on premixed charged compression ignition engine operating on mixture of non-fatty acid camphor oil and Polanga oil

Experimental investigation on premixed charged compression ignition engine operating on mixture of non-fatty acid camphor oil and Polanga oil

Computational Investigation of Advanced Compression Ignition with Wet Ethanol in an OP-2S

<div>Alcohol fuels have inherent properties that make them suitable candidates to replace conventional fossil fuels in internal combustion engines by reducing the formation of harmful emissions such as lifecycle carbon dioxide (CO<sub>2</sub>), nitrogen oxides (NO<sub>X</sub>), and particulate matter (PM). There is an increasing amount of work to use fuels such as ethanol or methanol in mixing-controlled compression ignition (MCCI) as a replacement for diesel fuel. However, employing these fuels in a strictly MCCI strategy results in an evaporative cooling penalty that lowers indicated fuel efficiency. This work proposes the use of an advanced compression ignition (ACI) strategy with a high autoignition resistant fuel, where a fraction of the fuel is premixed and autoignited in conjunction with a fraction of fuel that is burned in a mixing-controlled manner to achieve diesel-like efficiencies with significant emission reductions.</div> <div>A computational model for MCCI with diesel and wet ethanol in an opposed piston two-stroke (OP-2S) engine was validated against experimental data. Diesel and wet ethanol MCCI were then compared at a similar operating condition, where it was seen that wet ethanol provided a significant reduction in NO<sub>X</sub> emissions but resulted in a lower indicated efficiency. A triple injection strategy to enable ACI is then proposed by redesigning one of the injectors to enable compression stroke injections. The injector included angle, the injection split fractions, and injection timings of the triple injection strategy were varied to understand the impact of each on combustion performance and emissions. An optimal triple injection strategy based on simulation data was approximated and then simulated to compare to conventional diesel (i.e., MCCI with diesel) and MCCI with wet ethanol. ACI demonstrated a 3.5% point efficiency improvement over MCCI with wet ethanol, resulting in an efficiency that was the same as conventional diesel while still demonstrating nearly a 4 times reduction in NO<sub>X</sub> emissions.</div>

A comprehensive review of algal biodiesel for compression ignition engines: Challenges, advances, and future prospects

Biodiesel derived from microalgae and macroalgae, as a third-generation biofuel, presents a sustainable and renewable alternative for use in conventional diesel engines with minimal to no modifications. Despite extensive research available on algal biodiesel, there is a significant lack of progressive reviews specifically addressing its utilization in diesel engines, along with the influence of key operating parameters such as load, speed, injection pressure, injection timing, and compression ratio. This review aims to bridge this gap by investigating the physicochemical properties of algal biodiesel, along with its storage, transport, blending potential and compliance with emission norms. The study further analyzes combustion, performance, and emissions characteristics of algal biodiesel blends ranging from B10 to B100, identifying B20 as the most optimal blend due to its diesel-like combustion and performance characteristics and lower exhaust emissions under various engine conditions. For B20 blends, variations in peak in-cylinder pressure, maximum heat release rate, brake thermal efficiency, brake-specific fuel consumption, and exhaust gas temperature ranged from 0.9% to 6.5%, while oxides of nitrogen, carbon monoxide, hydrocarbons, and carbon dioxide emissions differed by 2.5–13% compared to diesel. The findings are backed by experimental validation, including uncertainty analysis to ensure the reliability and accuracy of the mentioned data. However, higher blend ratios tend to negatively impact engine combustion and performance while also increasing NOx emissions. To counteract these challenges, this review examines the role of fuel additives, advanced combustion strategies, and commercialization barriers, highlighting algal biodiesel's technical and environmental promise as a sustainable and efficient alternative fuel.

Simulation-Based Study of NH3/H2-Dual Fueled HCCI Engine Performance: Effects of Blending Ratio, Equivalence Ratio, and Compression Ratio Using Detailed Chemical Kinetic Modeling

Challenges associated with the homogeneous charge combustion ignition (HCCI) concept include combustion phasing control and a narrow operating window. To address the HCCI engine developmental needs, chemical kinetic solvers have been recently included in the commercial engine simulation toolchains like GT-Suite v2024 upward. This study investigates the feasibility of ammonia (NH3) and hydrogen (H2) as dual fuels in homogenous charge compression ignition (HCCI) engines, leveraging chemical kinetics modeling via GT-Suite software v2024. A validated baseline model was adapted with NH3/H2 injectors and simulated across varying blending ratios (BR), compression ratios (CR), air–fuel equivalence ratios (ER), and engine speeds. Results reveal that adding 10% H2 to NH3 significantly improves ignition. Optimal performance was observed at a CR of 20 and a lean mixture, achieving higher indicated thermal efficiency (about 40%), while keeping the intrinsic advantages of zero-carbon fuel. However, NOx emissions increased with higher ER due to elevated combustion temperatures. The study emphasizes the trade-offs between efficiency and NOx emissions under tested conditions. Finally, despite the single-zone model limitations in neglecting thermal stratification, this study shows that kinetic modeling has great potential for effectively predicting trends in HCCI, thereby demonstrating the promise of NH3/H2 blends in HCCI engines for cleaner and efficient combustion, paving the way for advanced dual-fuel combustion concepts.

Enhancing Specific Fuel Consumption Predictions in Compression Ignition Engine: A Taguchi Optimized Neural Network Approach for Diesel and Polymer Based Fuels

Enhancing Specific Fuel Consumption Predictions in Compression Ignition Engine: A Taguchi Optimized Neural Network Approach for Diesel and Polymer Based Fuels

GAS CHROMATOGRAPHY-MASS SPECTROMETRY ANALYSIS OF LANNEA MICROCARPA BIODIESEL

Lannea microcarpa (African grapes) is the specific seed selected for this study. The plant belongs to the family Anacardiacea and is found in the savanna and the drier forest zone of West Africa. The plant seed has 22-28% moisture content and a non-edible oil yield of 38 41%. Mechanical oil pressing was employed to extract the oil from Lannea microcarpa seed, and biodiesel was synthesized from the seed oil in two steps reactions of acid-catalyzed esterification and alkali-catalyzed trans-esterification at a reaction temperature of 600C- 650C. The percentage oil and biodiesel yield was found to be 46.15% and 90.63%wt respectively. Results from Similar research had slightly reported the GC-MS analysis of Lannea microcarpa biodiesel but none among these or any other published research from the literature has reported in detail the oil extraction, biodiesel production and GC-MS results and analysis of Lannea microcarpa biodiesel. In this work, biodiesel was characterized by GC-MS, and the methyl esters and other compounds present were identified and interpreted. Analysis of the GC-MS results showed that methyl oleate (37.04%), methyl palmitate (29.72%), methyl linoleate (11.05%) and methyl stearate (6.67%) as the predominant methyl esters. The result also reveals that three out of the four predominant methyl esters have zero double bonds, it is only methyl linoleate that has double bond; therefore, the biodiesel is considered to be saturated methyl ester. The unique combination of saturated and unsaturated fatty acid methyl esters in this biodiesel will have a positive impact on both the cold flow properties and stability of the fuel to oxidation, peroxidation, and polymerization reactions; this points out the reliability and viability of Lannea microcarpa biodiesel as an alternative fuel for compression ignition engines. The presence of high percentage of methyl oleate indicates the potential use of this biodiesel as a source of oleo chemicals or corrosion inhibitors in steel industries. All the findings were compared favorably with the results of other researchers.

Enhancement of compression ignition engine performance and emission reduction using pyrolyzed waste plastic oil blended with aluminum oxide nanoparticles

Abstract This research investigates the use of waste plastic fuel in compression ignition (CI) engines, focusing on two main objectives: producing pyrolysis plastic oil from waste plastic and reducing dependence on conventional CI engine fuels. The pyrolysis process involves heating low‐density polyethylene (LDPE) in a reactor at temperatures between 300°C and 500°C to generate plastic oil. Engine performance was evaluated using various blends of this oil, including 10%, 20%, and 30% mixtures with diesel. Additionally, 30 ppm of aluminum oxide (Al2O3) nanoparticles were mixed with 10% and 30% pyrolyzed waste plastic oil (WPO) to enhance fuel properties and engine performance. The study analyzed the impact of nanoparticles on engine efficiency and emissions, revealing that adding 30 ppm Al2O3 to all WPO blends improved overall performance compared to conventional diesel. Notably, the WPO 30 + 30 ppm Al2O3 blend significantly reduced emissions, with a 37.45% decrease in carbon monoxide (CO), a 22.5 ppm reduction in unburned hydrocarbons (HC), and a 33.23% reduction in smoke opacity. However, nitrogen oxide (NOx) emissions increased by 487 ppm compared to diesel.

Numerical Investigation of System Architecture and Engine Characteristics Effects on Gasoline Compression Ignition (GCI) Hybrid Heavy-Duty Truck Performance

Numerical Investigation of System Architecture and Engine Characteristics Effects on Gasoline Compression Ignition (GCI) Hybrid Heavy-Duty Truck Performance

Experimental investigation of compression ignition engine fuelled by pyrolyzed waste thermocol oil: a sustainable fuel approach

Abstract The increasing accumulation of plastic waste poses significant environmental challenges, necessitating the development of sustainable disposal methods. Pyrolysis is a viable approach to convert waste plastics into liquid fuels. This study investigated the catalytic pyrolysis of waste thermocol (expanded polystyrene) into waste thermocol oil (WTCO) using rice husk ash (RHC) and zeolite (ZeC) as catalysts and used as a heating source for biogas. A prototype pyrolysis reactor with a polymer-to-catalyst ratio of 0.1. The physicochemical properties of the obtained WTCO were analyzed and tested in a single-cylinder Kirloskar TV 1 compression ignition (CI) engine to evaluate its combustion, performance and emission characteristics. The Heat Release Rate (HRR) analysis indicated that the RHC-derived WTCO exhibited the highest HRR (143 MJ/kg-degree) and peak cylinder pressure (67 bar), enhancing the combustion efficiency. The brake thermal efficiency (33.94%) was superior because of its lower viscosity (1.96 cSt) and density (812 kg m−3), ensuring improved atomization. Emission analysis revealed higher nitrogen of oxides emissions (1324 ppm) due to increased combustion temperatures, while unburned hydrocarbons (42 ppm), smoke density (59.1 HSU) and carbon monoxide emissions were significantly reduced compared to diesel. These findings establish RHC-derived WTCO as a promising alternative fuel, contributing to sustainable energy solutions and efficient plastic waste management.

An Experimental Investigation of Combustion Stability in an Electric-Plug-Assisted Compression Ignition Methanol Engine

When an engine burns methanol, which has a high latent heat of vaporization, if the injection parameters are not set reasonably, the engine will exhibit high combustion instability at low speeds. Therefore, in this study, two pre-injections are set up in an electric-plug-assisted compression ignition methanol engine to investigate the effects of the pre-injection ratio and pre-injection timing on combustion stability and to provide a theoretical basis for the calibration of the injection of the engine at low speeds. The test results show that, at low speeds, the pre-injection ratio and pre-injection timing have a significant effect on combustion stability. They also show that, at low speeds and high loads, by regulating the pre-injection strategy, the bimodal phenomenon observed in the cylinder pressure of the compression ignition methanol engine can be weakened, and the cylinder pressure fluctuation caused by afterburning can be improved. Specifically, the maximum cyclic fluctuation of cylinder pressure was improved by 32.8%, the maximum cyclic fluctuation of the engine’s indicated average effective pressure was improved by 8.12%, and the maximum cyclic fluctuation of engine peak pressure was improved by 16.96%. The start point and combustion center of gravity data were centralized. The concentration of the start point and combustion center of gravity data improved by 6 °CA and 5.87 °CA, respectively.

Analyzing Carbon and Particulate Matter Emissions in Compression Ignition Engines with Biodiesel and Nanoparticle Additives

Pollutants from vehicles pose a direct threat to our ecosystem due to the emission of hazardous gases. The increasing urbanization of the world has led to higher consumption of petroleum products. These products, such as diesel and petrol, are derived from crude oil, which has limited reserves, and natural gas stocks are also limited. Countries with low or no fossil fuel reserves face significant shortages of gasoline, crude oil, and petroleum production and supplies. This study aims to evaluate the effects of using biodiesel as an additive in diesel engines for the analysis of carbon and particulate matter emissions. The results found that carbon emissions reduce 1.13% in biodiesel, 2.54% reduction in aluminum oxide and particulate matter emissions were 4.459 biodiesel 9.669% reduced in aluminum oxide with compared to diesel. Furthermore, the addition of nanoparticles to the biodiesel blend further reduced emissions.

Stability Assessment of Ethanol Added Algae-Biodiesel Blend for Naturally Aspirated CI Engines

This article investigates the preparation and stability of advanced biodiesel blends, specifically BD15E15 (70 % diesel, 15 % algae biodiesel, 15 % ethanol), aiming to optimise their properties for Compression Ignition (CI) engine applications. The research examines the synergistic effects of mechanical stirring and ultra-sonication on blend stability, focusing on the influence of emulsifier type (SPAN 80 and TWEEN 80), emulsifier concentration (0.5 % and 1 % v/v), stirring time (60, 120, and 180 minutes), and ultra-sonication duration (15 and 30 minutes). Twelve different blends were formulated and subjected to a seven-day stability assessment, primarily through visual observation of phase separation. The experimental results revealed that TWEEN 80, particularly at a concentration of 0.5 % v/v, significantly outperformed SPAN 80 in maintaining blend homogeneity. The most stable blend, achieved with TWEEN 80, was prepared using 120 minutes of mechanical stirring at 2000 RPM (Sample S8). Subsequent ultrasonication of this optimised blend further enhanced its stability. Notably, a 15-minute ultrasonication treatment yielded a more uniform mixture by improving the dispersion of biodiesel, ethanol, and diesel components, attributed to the cavitation effect. However, extending the ultrasonication duration to 30 minutes resulted in excessive heat generation, leading to increased ethanol evaporation and subsequent phase separation, thereby compromising blend stability. This study underscores the critical role of precise control over emulsifier selection, stirring parameters, and ultrasonication time in achieving stable biodiesel-ethanol-diesel blends. Major Findings: TWEEN 80 at 0.5 % v/v provided superior blend stability, with the optimal formulation (Sample S8) achieved using 120 minutes of mechanical stirring at 2000 RPM. Ultrasonication for 15 minutes further improved dispersion, but 30 minutes caused excessive heat, leading to ethanol evaporation and phase separation.

Effects of H2 substitution on combustion and emissions in ammonia/diesel compression ignition engine

Effects of H2 substitution on combustion and emissions in ammonia/diesel compression ignition engine