Fueled Compression Ignition Engine Research Articles

Use of butanol, pentanol and diesel in a compression ignition engine: A review

Using oxygenated alternative fuels in compression ignition (CI) engines is feasible for energy security problems and cli-mate change. Alcohols are regarded as alternative fuels for compression ignition engines because of their excellent physi-cochemical features, emission, and combustion characteristics. Research on alcohols and their additions has progressed significantly in recent years. Several researchers have examined the combined effect of higher alcohol with diesel and their impact and challenged that concentrations of higher alcohol reduce harmful particulate emissions in CI engines. This paper mainly focused on the performance and emissions properties of higher alcohols like butanol and pentanol. Alcohol has a low energy content, typically affecting engine brake-specific fuel consumption (BSFC). Low-temperature combustion (LTC) in compression ignition engines can lower NOx and smoke emissions, and improve the efficiency of the engine. LTC is done by combining higher alcohol with increased exhaust gas recirculation (EGR) rate and retarded fuel injection timing. The higher alcohol, along with the oxygen in the fuel reduces exhaust fumes, improves the air/fuel mixture by providing a longer ignition delay (ID), and can replace the fossil fuel like diesel (partially or whole) to allow efficient and clean combustion in CI engines. Finally, several significant findings and comments are provided regarding potential ave-nues for experimental research and future development. According to thorough analysis, bio-alcohols are considered to be a substitute fuel for CI engines.

Assessing combustion characteristics of alternative fuels in a CI engine by use of a wavelet-based analysis of engine vibration signals

In the current work, a wavelet-based approach for assessing combustion performance of alternative fuels in compression-ignition engines, indicated that changes in cylinder pressure amplitude were reflected by commensurate changes in a proposed parameter, with a maximum of a 9% variation. The proposed parameter, the wavelet transform coefficient maximum amplitude (WMA), successfully accomplished this for various engine conditions. The wavelet transform coefficient standard deviation (WSD), a second proposed parameter, was able to track changes in the rates of pressure rise associated with changes in load conditions and fuel type, with a maximum variation in the parameter of 7%. The approach was assessed by testing six fuels in a test engine unit. Thermodynamic property data and vibration signal data were recorded for each of the fuels tested, at six loading conditions. Subsequently, combustion performance was evaluated using traditional thermodynamic parameters and using the WMA and WSD via a MATLAB based algorithm. Thus, it was surmised that the proposed approach can form the basis for a vibration-based assessment of alternative fuel combustion performance in reciprocating engines.

A comparative study on combustion characteristics of PPC and RCCI combustion modes in an optical engine with renewable fuels

Application of renewable fuels in compression ignition engines provides one solution to reduce greenhouse gas emission in heavy-duty transportation sector. However, it is a big challenge to find a single alternative fuel to replace the traditional diesel under full load conditions. In this study, the combustion characteristics of two kinds of renewable fuels with different reactivity, namely methanol and hydrogenated catalytic biodiesel (HCB), were investigated in an optical engine under partially premixed combustion (PPC) and reactivity-controlled compression ignition (RCCI) modes, respectively. A two-color (2C) method was employed to quantify the in-flame soot formation. Meanwhile, the flame oscillation phenomenon was captured and evaluated. The results indicate that the RCCI mode exhibits reduced peak cylinder pressure, resulting in smoother and more stable combustion compared to that of the PPC mode. Moreover, the more uniform fuel distribution in the RCCI mode further decreases soot formation from the blended fuel. Additionally, with increasing methanol proportion, the rise in oxygen content within the blended fuel significantly reduces soot formation. The flame oscillations are primarily related to the rate of cylinder pressure variation. Under PPC mode, multi-point autoignition causes a rapid increase in cylinder pressure, leading to larger oscillation amplitudes (M15: 0.268, M25: 0.772). Conversely, under the RCCI mode, the heat release process is more stable, resulting in weaken oscillations (M15: 0.161, M25: 0.064) compared to that of PPC.

Ignition Delay Period Prediction for Compression Ignition Engines Fueled with Ethanol/Diesel Blends

Ignition Delay Period Prediction for Compression Ignition Engines Fueled with Ethanol/Diesel Blends

The Green Energy Effect on an HCCI Engine from Used Cooking Oil-based Biodiesel from Malaysia

Emissions from internal combustion engines (ICEs) significantly impact the environment, leading continents worldwide to work towards reducing them. The industry is increasingly leaning towards electric powertrains. However, power plants still utilize ICEs as generators, contributing to global pollution. Consequently, ICE emissions are garnering international attention. Alternatives like the Homogeneous Charge Compression Ignition (HCCI) engine and biodiesel fuels are being explored. HCCI engines have not been extensively tested with Used Cooking Oil (UCO) biodiesel. This study investigates the performance and emissions of HCCI engines using UCO-based biodiesel. This study tested an air-cooled, single-cylinder, 4-stroke diesel engine operating at 3600 rpm with a displacement of 0.219 liters. The HCCI mode was activated during preheating and run at 2700 rpm under varying biodiesel blend percentages and intake temperatures. In HCCI mode, brake-specific fuel consumption (BSFC) increased, peaking at a 90°C intake temperature. Diesel fuel in-cylinder pressure reached a maximum of 81 bars at 90°C, decreasing to 79 bars at 70°C. The HCCI mode resulted in lower NOx, CO, and UHC emissions. Higher biodiesel blend ratios further reduced CO emissions. Raising the intake air temperature to 90°C lowered NOx emissions by 96.66%, from 150 ppm to 5 ppm. Using green energy sources as fuel in HCCI engines significantly reduced emissions in this study, suggesting their potential as a future fuel for advanced engines.

Multi-objective optimization of a dual fuel CI engine powered with syngas and pilot diesel using TLBO algorithm: A metaheuristic approach

Abstract The thermochemical conversion of biomass into producer gas presents an attractive alternative fuel option for compression ignition (CI) engines, making biomass gasification a critical driver for achieving sustainable development goals. Considering the application of producer gas (PG) in CI engine, the most potential gases include H2 and CO as main fuel compounds and it is crucial to comprehensively understand the impact of these two gas components on the engine behaviour. Nowadays, artificial intelligence-powered models are frequently applied for simulating engines that run on a single type of fuel. However, their usage is not as common when it comes to modeling dual-fuel CI engines run on synthetic producer gas or syngas. The present study explores the feasibility of optimizing operational parameters, such as engine load and syngas composition, in improving the efficiency and lowering the levels of pollutants emitted by a 3.5 kW CI engine operated under dual fuel (DF) mode using syngas as primary fuel and diesel as pilot fuel. The performance and emission characteristics of syngas (H2:CO) is examined by studying its behaviour in four different combinations. The compositions of syngas are prepared based on the volumetric percentage of the H2 and CO and is inducted into the combustion chamber using a novel venturi-type air-gas mixer. In the present study, an intelligent metaheuristics-based optimization algorithm i.e., Teaching–Learning Based Optimization (TLBO) is developed and introduced, to develop a predictive model within constrained range of engine operating conditions. Further, the algorithm is used to estimate multiple engine performance characteristics simultaneously viz., brake thermal efficiency (BTE), unburned hydrocarbons (HC), and carbon monoxide (CO). The resultant findings identify the optimal engine load of 68.87% and the ideal syngas composition of 63.9% H2 and 49.5% CO as key parameters for maximizing engine efficiency while minimizing exhaust emission. At these optimized operating condition, 19.49% BTE is observed, while HC and CO emission was found to be 384.6 ppm and 445.33 ppm respectively. This shows the effective and efficiency of the proposed algorithm.

A Review on Synthesis, Combustion, Performance and Emissions of Compression Ignition Engine Fueled by Waste Cooking Oil Based Biodiesel

A Review on Synthesis, Combustion, Performance and Emissions of Compression Ignition Engine Fueled by Waste Cooking Oil Based Biodiesel

Experimental evaluation of a diesel engine using amide-functionalized carbon nanotubes as additives in commercial diesel and palm-oil biodiesel

Nanomaterials used as additives to diesel, biodiesel, and its blends have shown promising results in improving thermal efficiency and reducing pollutant emissions in compression ignition engines. However, the stability of dispersions has been noted in the literature as a primary challenge to the effective use of nanomaterials as fuel additives. Between nanomaterials used as additives to fuels are carbon nanotubes (CNTs). These carbonaceous materials have shown positive and negative results concerning engine performance and emissions, and the differences could be associated with the dispersion stability of the nanomaterials in the fuel. Therefore, there is still much uncertainty regarding the relationship between the stability of nanomaterial dispersion and the impact of nanofuels on engine performance. Specifically, the current literature lacks sufficient information regarding the impact of incorporating amide-functionalized carbon nanotubes (CNT) on the stability of diesel-biodiesel blends and their influence on particulate matter emissions in ICE. In this study CNT and amide-functionalized CNT were dispersed in Colombian commercial diesel (10 % vol. of palm oil biodiesel) and palm oil biodiesel, and its stability was evaluated. The most stable blends were used in a stationary Ignition Compression Engine (ICE) to evaluate the impact of the nanomaterials on thermal efficiency and pollutant emissions. Results show that it was not possible to disperse CNT in Colombian commercial diesel (10 % vol. of palm oil biodiesel and 90 % vol. of petroleum diesel) due to its high rate of agglomeration and sedimentation. In contrast, the opposite behavior was shown using biodiesel as a base fuel. An amide functionalization of the CNT process was carried out to generate a repulsion of CNT and improve its stability in commercial diesel fuel. Amide-functionalized carbon nanotubes (CNTF) were obtained using pristine CNT and Oleylamine as nitrogen functional group precursors. X-ray Photoelectron Spectroscopy confirmed the amide functional groups on the CNT surface, and a loss weight of 14 % was identified in the temperature range of 150–550 °C, indicating a high grade of functionalization. Functionalized and non-functionalized CNT were dispersed in Colombian commercial diesel and palm oil biodiesel using a concentration of 100 mg/L to evaluate the dispersion's colloidal stability. This stability was examined for three days by visual inspection and variation of the hydrodynamic diameter using dynamic light scattering. The most stable dispersions were prepared at two concentrations (50 and 100 mg/L) and used as fuels in a stationary compression ignition engine. Colloidal stability was enhanced when CNTF were dispersed in diesel compared to the unstable, pristine CNT dispersion. However, in biodiesel, the dispersion behavior of the CNT and CNTF was similar. Compared to diesel, the diesel-CNTF dispersion did not considerably improve the engine´s thermal performance at 6 kW, and only a minor gain was observed at 12 kW at a concentration of 100 mg/L. However, at 6 kW, they reduced particulate matter emissions by up to 39.8 %. In the case of biodiesel, utilizing both functionalized and non-functionalized carbon nanotubes as additives, the thermal efficiency was increased, and CO emissions decreased.

Experimental and numerical study on ammonia fueled compression ignition engine

Experimental and numerical study on ammonia fueled compression ignition engine

Effects of diesel injection timing and methanol substitution ratio on combustion and exhaust emission characteristics of a dual fuel compression ignition engine

Effects of diesel injection timing and methanol substitution ratio on combustion and exhaust emission characteristics of a dual fuel compression ignition engine

Production of biofuel from AD digestate waste and their combustion characteristics in a low-speed diesel engine

Anaerobic digestion biogas plants generate large amounts of digestate that cannot always be valorised as fertilizer. This study proposes an alternative use through pyrolysis of the digestate for the production of liquid fuels for compression ignition engines. The digestate pyrolysis oil (DPO) and two types of biodiesel were produced and mixed with different alcohols. A total of five blends of DPO, biodiesel and alcohol were prepared and characterized, showing that their acidity and viscosity were higher than for pure diesel, and their heating value was lower. Blends containing 60 % biodiesel, 20 % DPO, and 20 % butanol were then tested in an engine, showing that the maximum in-cylinder pressure and heat release rate were 4.6 % and 3 % lower, respectively, compared to diesel, and the engine thermal efficiency at full load was 6–8% lower. The nitric oxide and smoke emissions were 7 % and 40 % lower, respectively, but the carbon dioxide emissions were 7–10 % higher than with diesel. The blends showed retarded start of combustion by 1.5° crank angle, which delays the ignition by about 6.4 %. This study concludes that blends can be used as a fuel for agriculture and marine diesel engines, although their viscosity should be reduced by improving the pyrolysis conditions.

The improvements of a diesel engine fueled with renewable and sustainable diesel/n-butanol/polyoxymethylene dimethyl ethers blended fuels at high altitudes

Atmospheric conditions at high altitudes deteriorate combustion in the cylinder of compression ignition (CI) engines, severely degrading engine performance and increasing soot emissions. The use of oxygenated fuels as an alternative fuel to diesel is an effective solution to improve performance and reduce emissions of highland CI engines. Before optimizing a highland CI engine, it is necessary to determine the law of influence of oxygenated fuels on the performance and emission characteristics of the engines. This paper focuses on the effect of diesel/n-butanol/polyformaldehyde dimethyl ether blends on the combustion, performance, and emission characteristics of a CI engine at different simulated altitudes (0 m, 2000 m, 3000 m, and 4000 m). First, a three-dimensional computational fluid dynamics (3D-CFD) simulation model was developed and validated by experimental results. Second, the 3D-CFD model coupled with a chemical kinetic mechanism including 164 species and 643 reactions was used to simulate the combustion process in the cylinder under different operating conditions. The results showed that the high-altitude environment increased the cylinder temperature, peak heat release rate, ignition delay, soot emissions, HC emissions, and brake specific fuel consumption, and reduced BTE, and NOx emissions of the CI engine compared with the plains. At the same altitude, the use of n-butanol and PODE3 provided oxygen for in-cylinder combustion, which somewhat promoted more complete combustion in the cylinder, reduced HC and soot emissions and increased BTE. Although the use of oxygenated fuels in highland CI engines elevated NOx emissions, the problem could be solved by methods such as LTC and SCR. Overall, n-butanol and PODE3 are promising alternative fuels for highland CI engines, mitigating to some extent the problems of higher soot and HC emissions and lower BTE associated with high-altitude environments.

Evaluation of Ecological Parameters of a Compression Ignition Engine Fueled by Diesel Oil with an Eco Fuel Shot Liquid Catalyst

This article discusses the potential applications of the Fuel Shot liquid catalyst in compression ignition (CI) engines for reducing toxic substances in exhaust gases. Incorporating catalysts into fuel can optimize the combustion process, consequently reducing the emission of toxic substances into the atmosphere. Toxic compounds, such as nitrogen oxides, particulate matter, and hydrocarbons, adversely affect flora and fauna. Various methods are known for reducing their concentration in engine exhaust gases, one of which is the Fuel Shot liquid catalyst. The authors conducted experiments on a Fiat 1.3 JTD engine with a Common Rail system. The results indicate that the application of the liquid catalyst reduces the content of nitrogen oxides and hydrocarbons in the exhaust gases and slightly decreases fuel consumption. Additionally, investigations were carried out on the engine’s injection apparatus, which was fueled with modified fuel. The findings demonstrate that the fuel additive does not affect the wear of precision parts of fuel injectors and high-pressure pumps.

A sustainable model using RSM and MCDM techniques to evaluate performance and emission characteristics of a diesel engine fueled with diphenylamine antioxidant and CeO2 nanoparticle additive biodiesel blends

Overconsuming fossil fuels has worsened global warming and air pollution, requiring us to investigate alternate fuels for compression ignition engines. Biodiesel is a renewable fuel and environmentally favorable. Biodiesel's most significant disadvantage is increased nitrogen oxide (NOx) emissions. The intent of the present study was to examine the impact of antioxidant diphenylamine (DPA) and nanoparticle ceria (CeO2) additive inclusion in a B30 blend on engine performance and exhaust emission characteristics. For this study, diesel, Jatropha biodiesel (B30), 100 ppm of antioxidant diphenylamine (50 ppm) with ceria nanoparticle (50 ppm) is added to the B30 blend named as B30+DPA100 and antioxidant diphenylamine (50 ppm) with ceria nanoparticle (50 ppm) is added to the B30 blend named as B30+DPA50+CeO250 fuel blends has been used. A hybrid response surface methodology and multi-criteria decision-making techniques (entropy method, TOPSIS, and VIKOR) have been used to develop a sustainable model and find the optimal setting of input parameters in terms of ranking. From experimental findings, the inclusion of antioxidants (DPA) and nanoparticle (CeO2) at 50 ppm to B30 significantly reduced NOx emission. The brake-specific fuel consumption and NOx have been found reduced by 5.67% and 18.87%, respectively, for B30+DPA50+CeO250 as compared to B30. At the same time, brake thermal efficiency increased by 1.01%. The brake mean effective pressure and maximum cylinder pressure) have been found increased by 0.68% and reduced by 4.52%, respectively, for B30+DPA50+CeO250 as compared to B30. The alternative ranking of the input parameters has been found fuel injection pressure (300), compression ratio (17), and load (12) as Rank 1 for TOPSIS and VIKOR. Therefore, the B30+DPA50+CeO250 blend is appropriate for improving diesel engine performance and diminishing exhaust emissions.

The combined effect of hydrogen enrichment and exhaust gas recirculation on the combustion stability, performance and emissions of CI engine energized by algae biodiesel

The scarcity of fossil fuels, the rising cost of liquid fuels, and the wide pollution footprint of conventional fuels all motivate scientists to seek out new approaches. This experimental study aims to explore the performance and emissions of compression ignition (CI) engines by introducing hydrogen into a biodiesel blend derived from algae. According to this study, the superior thermal properties of hydrogen associated with algal biodiesel have a significant impact on the performance and emissions of dual-fuel engines. The effect of hydrogen substitution rates of 10.4, 21.6, 32.4, 43.2, and 54 g per hour (g/h) on pure algae biodiesel was investigated. In comparison to diesel, the algae biodiesel reduces unburned hydrocarbons (UHC) and carbon monoxide (CO) emissions by 4.1% and 8.82%, respectively, while nitrogen oxide (NOx) emissions increase by 18%. Diesel was found to have increased brake thermal efficiency (BTE) and decreased brake specific energy consumption (BSEC) compared to biodiesel. With the addition of pure biodiesel, the 43.2 g/h H2 substitution rate produces a maximum thermal efficiency of 1.92% and a 9.5% decrease in brake-specific energy consumption compared to diesel at maximum load. Compared to diesel, the emission attributes of UHC, CO, and smoke opacity decreased by about 45%, 48%, and 41%, respectively. However, NOx emissions increase by about 36% compared to diesel due to the higher flame temperature and carbon-free fuel of hydrogen and oxygenated biodiesel. The induction of 15% exhaust gas with B100 + 43.2 g/h H2 reduces NOx by about 31% in comparison to B100 + 43.2 g/h H2 without exhaust gas recirculation (EGR). This is primarily attributable to the high oxygen dilution and specific heat capacity of burned gases, which result in a decrease in peak cycle temperature. Compared to diesel, B100 + 43.2 g/h H2 increased the cylinder pressure and heat release rate by about 1.86 and 4.29%, respectively. As a result of its high energy density, hydrogen improves overall energy utilization and engine performance. Hydrogen's rapid flame speed and wide flammability range contribute to the efficient and complete combustion of the algae fueling the CI engine. As well as showing outstanding performance, dual fuel CI engines have the potential to significantly contribute to lowering emissions. Finally, it was determined that using algae biodiesel and exhaust gas recirculation with hydrogen substitution in diesel engines can significantly reduce emissions while increasing efficiency.

Impact of Hydrogen on Emission Reduction in a CI Engine when Fuelled with Blends of Diesel-Waste Cooking Biodiesel

Waste utilisation and emission of greenhouse gases are two of the world's most pressing challenges today. This study seeks to solve the problem generated by the disposal of Waste Cooking Oil (WCO) as a tiny step forward in contributing to the reduction of waste disposal. WCO has a high potential as a bio fuel for internal combustion engines, hence it was chosen for this investigation. WCO of 20% and diesel 80% is used. This study looks at the performance, combustion and emission parameters of a dual fuel compression ignition engine running on WCO biodiesel with a hydrogen additive at atmospheric condition. The parametric study include variation in engine load (0-18 kg) and hydrogen flow rate (3, 6, 9 LPM). The experiment was conducted on a four-stroke diesel (computerized), single cylinder, water cooled power at 5.2 kW at 1500rpm Kirloskar engine. From the experiment overall parametric variation of 35.38%, 34.06% and 32.37% of brake thermal efficiency was obtained and emission was observed. However, with increase of hydrogen flow rate resulted in increased engine performance, increase in CO, NOx and reduction in emission of UBHC and CO2.

Assessment and usability of Jatropha biodiesel blend with phenolic antioxidant to control NOx emissions of an unmodified diesel engine.

The excessive utilization of fossil fuels has worsened global warming and exacerbated the levels of air pollution in the environment, forcing us to consider alternative fuels for compression ignition engines. The current research aims to explore the possibilities of renewable fuels outperforming diesel fuel in terms of combustion, performance, and emission characteristics. Biodiesel is an environmentally friendly and renewable alternative fuel. The major drawback of biodiesel is the significant rise in nitrogen oxide (NOx) emissions. The main novelty and objective of this research is to investigate the performance and emission characteristics of variable compression ratio diesel engine using DPA antioxidant additive. For this investigation, diesel, Jatropha biodiesel (B30) and 100 ppm of phenolic antioxidant diphenylamine (DPA) blended with B30 have been used as fuel named B30+DPA100. From experimental outcomes, the inclusion of diphenylamine to B30 blend resulted in brake-specific fuel consumption (BSFC) and exhaust gas temperature (EGT) being reduced by 8.86% and 4.12%, respectively, compared to B30. Simultaneously, there was a 1.11% increase in brake thermal efficiency (BTHE). The B30+DPA100 fuel blend demonstrates effective control over NOx and other emissions. The emissions of NOx, carbon monoxide (CO), hydrocarbon (HC), and smoke from the B30+DPA100 blend have shown a reduction of 6.8%, 5.34%, 7.86%, and 15.67%, respectively, when compared to diesel. However, there has been an increase in carbon dioxide (CO2) by 7.8%. One notable advantage of the B30+DPA100 blend is the significant decrease in NOx emissions. Additionally, the cylinder pressure for B30+DPA100 has been lowered by 4.93% compared to B30. On the other hand, the net heat release rate (NHR) has experienced a 1.72% increase. The particle size of different elements present in the crankcase oil has been calculated by Zetasizer Nano. The analysis revealed varying particle sizes for different elements in the crankcase oil: aluminum (2.724 μm), chromium (2.78 μm), iron (2.423 μm), and lead (2.587 μm).

Investigation of performance, combustion and exhaust emission characteristics of a compression ignition engine fuelled with diesel-kerosene-ethanol-hydrogen strategies

The current investigation acmes the ascendancy of ethanol on the performance, combustion and exhaust emissions of adulterated diesel fuelled compression ignition engine. Diesel adulteration by kerosene results in an adverse effect on performances and carbon emissions of the engine, but significantly reduces oxides of nitrogen. A small amount of ethanol incorporation into the adulterated diesel avowedly improves the performance, combustion and exhaust emissions of the engine. To this end, the engine is further modified for injecting hydrogen to reveal the competency of five different strategies along with 85% diesel, 5% kerosene and 10% ethanol blended fuel in volumetric proportion. The small amount of hydrogen enrichment aids in the improvement of brake thermal efficiency (up to 3.2%), brake specific energy consumption (up to 3.1%), in-cylinder pressure, heat release rate, brake specific hydrocarbon (up to 50.1%), brake specific carbon monoxide (up to 50.5%) and brake specific particulate matter (up to 44.8%) emissions.

Experimental Investigation of Compression Ignition Engine Combustion, Performance, and Emission Characteristics of Ternary Blends with Higher Alcohols (1-Heptanol and n-Octanol)

Concerns about the depletion of petroleum reserves and rising pollution led researchers to search for alternate and environmentally compatible fuels for compression ignition engines. As an excellent alternative fuel additive to biodiesel–diesel blends, higher alcohol exhibits outstanding fuel properties (such as high energy content and cetane number) and can operate in diesel engines without requiring engine changes. This study focuses on investigating the ternary blends comprising higher alcohols, namely 1-heptanol and n-octanol, in hybrid biodiesel (animal fat oil–rice bran oil–cottonseed oil) and diesel on compression ignition engine characteristics. The performance, combustion, and emissions of a diesel engine fuelled with mono (D100), binary (B20), and ternary fuel blends (B20H10, B20H20, B20O10, and B20O20) were analysed at a constant engine speed of 1500 rpm. The test fuels met the American Society for Testing and Materials standards for fuel properties and exhibited stable behaviour during testing. Experimental results showed that at 100% load, the least brake-specific fuel consumptions for diesel fuel, B20, B20H10, B20H20, B20O10, and B20O20 were 254.1 g/kWh, 302.14 g/kWh, 281.25 g/kWh, 310.94 g/kWh, 292.8 g/kWh, and 313.80 g/kWh, respectively. Meanwhile, the maximum brake thermal efficiency values were obtained as 38.65%, 37.01%, 37.76%, 36.84%, 37.12%, and 36.38%, respectively. At 100% load, the peak heat release rates for diesel, B20, B20H10, B20H20, B20O10, and B20O20 were found to be 64.65 J/deg, 59.07 J/deg, 62.34 J/deg, 56.12 J/deg, 57.95 J/deg, and 51.9 J/deg, respectively. The addition of 1-heptanol and n-octanol as oxygenated additives into the ternary blend resulted in decreased carbon monoxide and unburned hydrocarbon emissions while increasing carbon dioxide and nitrous oxide emissions compared to diesel fuel. Overall, the study concludes that ternary blends with 1-heptanol and n-octanol as additives improve performance and combustion behaviour and reduce exhaust emissions compared to binary blends.

Investigation of the drop-in capabilities of a renewable 1-Octanol based E-fuel for heavy-duty engine applications

This article presents the results of an investigation of neat 1-Octanol and its blends with Diesel, which can be potential drop-in fuels for heavy-duty compression ignition engines. Fuel blends consisting of 10 %, 20 %, and 30 % 1-Octanol by volume in Diesel, including neat 1-Octanol, were investigated for ignition and combustion performances. The ignition behavior was assessed using a constant-volume combustion-chamber-based ignition tester. The experimental investigation was conducted on a heavy-duty single-cylinder engine by varying the combustion center. In addition, injection-rate shaping was performed to understand the effects of various injection-rate shapes, namely square, ramp, and boot rate shapes, on the performance of neat 1-Octanol.The ignition tester results indicated an increased ignition sensitivity of neat 1-Octanol towards the chamber pressure and temperature compared to that of Diesel. At an elevated chamber temperature (650 °C) and pressure (20 bar), the ignition delay of neat 1-Octanol approaches closer to that of Diesel. Engine experiments revealed an improved thermal efficiency with neat 1-Octanol and its blends by up to 1.2 %, owing to their improved mixture homogenization capabilities. Furthermore, neat 1-Octanol and its blend led to a drastic reduction in smoke and carbon monoxide. In addition, it results in the highest peak during the premixed heat release, and with a square injection-rate shape, an additional minor improvement in thermal efficiency was observed. The relative changes in carbon monoxide and hydrocarbon emissions between the injection-rate shapes were negligible. At higher load, the boot-rate shape results in lower NOx formation than the square-rate shape at an almost identical thermal efficiency. Overall, the 10 % 1-Octanol, 20 % 1-Octanol and 30 % 1-Octanol blends, which fulfill the Cetane number requirements for the given fuel norms, can be used as drop-in fuels, as they exhibit a comparable or even better performance than Diesel.