Brake Thermal Efficiency Research Articles

Investigation of dual impact of nanoparticles-ethanol as additive to biodiesel-diesel fuel on an engine using artificial neural network prediction model

This paper investigates effects of the dual approach of adding nanoparticles and ethanol to palm biodiesel-diesel fuel at varied percentage as additive. Four samples namely: E10(100) B20, E15(100) B20, E10(100) B50, and E15(100) B50 were investigated on a single cylinder L70N Yanmar engine at constant speed of 2500 rpm under three load categories of 25 %, 50 % and 75 % for each sample. The experimental data was then feed-in as training data to develop an Artificial Neural Network (ANN) using the feed-forward back propagation algorithm (FFBP) and applying the Levenberg-Marquardt training pattern. Four (4) inputs were used viz: engine load, fuel, additive and cetane number. Correlation coefficient (R) and determination coefficient (R2) were used to validate performance of the network with two set of four hidden layers while targeting 5 outputs viz: BTE, HC, CO, NOx, and smoke. Experimental results indicate that at 25 % load the Brake Thermal Efficiency (BTE) values of samples E10(100) B20, E15(100) B20, E10(100) B50, and E15(100) B50 were 10.131 %, 14.972 %, 13.945 %, 14.091 % while at 50 % load it was 18.201 %, 25.101 %, 23.046 %, 23.779 % and at 75 % BTE values was 23.779 %, 32.011 % and 30.826 % which showed engine performance can be improved by magnetite nanoparticles addition with ethanol to biodiesel-diesel fuel up to 7.4 % in terms of BTE compared to only biodiesel-diesel blend fuel; emission was noticeably reduced for tested gases compared to previous literatures. The validated ANN results range 0.99350 to 0.99975 and indicated an acceptable level for the ANN prediction model for BTE. ANN exhaust emission prediction implicated smoke and NOx target performance was most accurate with R and R2 values at 0.9942, 0.9984, and 0.9980, 0.9960 respectively which indicated minimal error and hence the ANN model was satisfactory.

Effect on minor addition of aromatic (benzyl alcohol) and diethyl ether in Calophyllum inophyllum blended diesel fuel in a CI engine operates by hydrogen energy as a secondary fuel

Strict regulations on vehicle emissions are in place to lessen pollution and environmental damage. The depletion of fossil fuels also threatens energy security. Renewable, cleaner-burning and sustainable fuels could aid the researcher in solving these problems. Because of their limited supply, renewable fuels cannot resolve the issue independently. Therefore, much research is being done on enhanced combustion technologies, such as dual-fuel engines, homogenous charge compression ignition, and low-temperature combustion. The Calophyllum inophyllum oil (P20) mixed with diesel, diethyl ether, and aromatic alcohol (benzyl alcohol) was tested in this study using a dual-fuel engine. Hydrogen gas is added to the air intake manifold as a second energy source. Aromatic alcohol is an organic fuel that can be produced naturally by hydrolysis of lignin. The OH hydroxyl group is attached to the aromatic ring and promotes free radical propagation. Minor addition of oxygenates affects the performance, combustion, and emission of engines operating on various loads. Maximum brake thermal efficiency and lower brake-specific fuel consumption were observed with 20 % aromatic alcohol, 32.45 %, and 0.2 kg/kW-hr, respectively. Brake thermal efficiency improved to 6.54 % compared to neat diesel. Reduction in brake-specific fuel consumption by 28 % compared to diesel fuel. Compared to other blends, aromatic alcohol additions are linked to reduced smoke, HC, and CO emissions. However, using aromatic alcohol results in slightly increased nitrogen oxide emissions compared to diesel. Blends of biofuel and benzyl alcohol have shown favorable effects in terms of enhanced combustion, reduced emissions, and increased efficiency.

Study of single and split injection strategies on combustion and emissions of hydrogen DISI engine

Hydrogen energy shows excellent potential as an alternative fuel for internal combustion engines (ICE) in terms of cleanliness and efficiency. However, the specificity of hydrogen density and diffusion rate leads to further optimization of the working process of the hydrogen direct injection spark ignition (DISI) engines. In this study, the effects of single injection and split injection strategies on the combustion and emissions of a hydrogen DISI engine were investigated at medium/low load. The specific results showed that premature hydrogen injection could trigger pre-ignition events, and it was appropriate to set the earliest hydrogen injection timing to 180° CA BTDC after the intake valve closing. For the single injection strategy, the brake thermal efficiency (BTE) increased first and then decreased with the delay of the start of injection (SOI). When SOI = 100° CA BTDC, the optimal BTE (36.1 %) could be obtained, and nitrogen oxide (NOx) emissions could still be limited to less than 0.1 g/(kW·h). For the split injection strategy, Delaying the secondary end of injection (SEOI) beyond 30° CA BTDC rapidly worsened NOx emissions to over 1.5 g/(kW·h). Delaying SEOI achieved higher efficiency but slightly worse the coefficient of variation COVIMEP than the single injection strategy. In addition, increasing the secondary injection mass fraction (SIMF) to 30 % could achieve an 18 % higher peak heat release rate than a single injection and shorter combustion duration. However, over 20 % SIMF resulted in an increase of NOx emissions to over 4 g/(kW·h). The energy distribution indicated that adjusting the injection strategy to increase BTE was mainly achieved by reducing power of heat loss (PHL).

Performance and emission characteristics of a diesel engine fuelled by biodiesel from black soldier fly larvae: Effects of synthesizing catalysts with citric acid

Biodiesel has several environmental benefits, such as biodegradability, renewability and lower soot emissions. However, biodiesel has undesirable properties such as higher viscosity and density and low calorific value compared to petroleum diesel, resulting in high Brake Specific Fuel Consumption (BSFC), reduced Brake Power (BP) and increased NOX emissions creating an environmental concerns in biodiesel development. This study investigated the effects of synthesizing transesterification catalysts (CaO and NaOH) with Citric Acid (CA) on the quality of biodiesel and biodiesel blends produced from Black Soldier Fly Larvae (BSFL) (Hermetia Illucens). The quality of biodiesel and blends was determined based on fuel properties, engine performance and emission composition characteristics. The tests were performed on a single-cylinder, four-stroke, Compression Ignition (CI) diesel engine at five loads at a constant speed of 1500 rpm. The results showed that synthesizing the catalysts with CA significantly affected the fatty acid profile of the biodiesel compared to physical fuel properties. B100 (pure BSFL biodiesel) exhibited higher BSFC by 10.57–13.97 % and lower BP by 4.21–7.83 % than diesel fuel. However, the Brake Thermal Efficiency (BTE) of biodiesel was higher than that of diesel fuel by 0.82–4.34 % at maximum load. Synthesizing catalysts with CA improved the viscosity of biodiesel by 0.93–2.81 % and effectively reduced NOX, HC and Smoke opacity by 2.23–3.16 %, 4.95–5.83 % and 20.51–41.15 %, respectively.

Comparison of machine learning algorithms for predicting diesel/biodiesel/iso-pentanol blend engine performance and emissions

In this study, machine learning techniques, namely artificial neural network (ANN), support vector machine (SVM), and extreme gradient boosting (XGBoost), were used to comprehensively evaluate engine performance and exhaust emissions for different fuel blends. To obtain valuable insights on optimizing engine performance and emissions for alternative fuel blends and thus contribute to the advancement of knowledge in this field, we focused on iso-pentanol ratios while maintaining the biodiesel ratios constant. The maximum brake thermal efficiency (BTE) values for the diesel (30.13 %), D85B10P5 (29.92 %), D80B10P10 (29.89 %), and D70B10P20 (29.79 %) blends were achieved at 1600 rpm. At 1600 rpm, the brake-specific fuel consumption (BSFC) values for the diesel, D85B10P5, D80B10P10, and D70B10P20 blends were 189.93, 200.93, 202.93, and 203.95 g kWh−1, respectively. In engine performance prediction, the ANN model exhibited superior performance, yielding regression coefficient (R2), root mean square error, and mean absolute error values of 0.984, 0.411 %, and 0.112 %, respectively, in BTE prediction, and 0.958 %, 6.9 %, and 2.95 %, respectively, in BSFC prediction. In exhaust gas temperature prediction, the SVM model exhibited the best performance, yielding an R2 value of 0.981. Although all models successfully predicted NOx emissions, the ANN model exhibited the best performance, achieving an R2 value of 0.959. In CO2 and hydrocarbon estimation, the XGBoost model exhibited the best performance, yielding R2 values of 0.956 and 0.973, respectively. Therefore, the ANN model can be used to accurately predict engine performance, and the XGBoost model can be used to accurately predict emission parameters.

Enhancing performance characteristics of biodiesel-alcohol/diesel blends with hydrogen and graphene nanoplatelets in a diesel engine

The pursuit of ecologically friendly and sustainable energy solutions is currently at the forefront of scientific study and technological advancements. The replacement of fossil fuels is a serious challenge in diesel engines. Furthermore, several researchers are concerned about lower-rate hydrogen enrichment and NOx emissions. In the current study, 50 mg/l of graphene nanoplatelets (G) and 10% of n-Butanol are used as additives in sterculia foetida biodiesel-diesel blends, along with H2 supply (at a flow rate of 3 and 6 lpm) as a secondary fuel, to improve the overall performance and reduce emissions of a single-cylinder, four-stroke, compression ignition engine. The combination of 20% biodiesel is blended in 80% diesel (B20), 50 mg/l of G included B20 (B20G50), 10 vol % of n-Butanol (on a volume basis) added in B20G50 blend (B20G50+n-Bu10) are used as piloted fuel. Besides, hydrogen enriched with air as a secondary fuel and B20G50+n-Bu10 fuel blend supplied as piloted fuel (B20G50+n-Bu10+3H2, and B20G50+n-Bu10%+6H2) are fueled to determine the performance, combustion, and emission characteristics of a CI engine. The addition of G and n-butanol in a B20 blend with a higher flow rate of H2 enrichment improved performance (Brake thermal efficiency increased by 7.54%, and Brake specific fuel consumption decreased by 20.75%). In contrast, the combustion parameters such as cylinder pressure and Heat release rate are improved by 9.8 and 6.23% at 100% load for the same blend. In contrast, emission characteristics of Carbon monoxide, Hydrocarbons, and smoke opacity are lowered by 19.75, 24.86, 9.58, and 8.8%, respectively, at higher loads as compared to the B20 blend. The higher heating value, improved atomization characteristics, superior flame velocity of H2, greater thermal diffusivity, the catalytic effect of nanoplatelets, and higher oxygen level of n-butanol improved engine performance, combustion, and decreased emission characteristics on diesel engines with no engine modifications. The outcomes of this research may be beneficial to run stationary engines used in various industrial sectors.

Effects of methanol direct injection and high compression ratio on improving the performances of a spark-ignition passenger car engine

The high octane number and high latent heat of vaporization of methanol are beneficial to suppress knock and consequently increase compression ratio (CR) of spark ignition engines, and thus improve the thermal efficiency. Few preious research on methanol engine combuston and performances have been conducted based on spark-ignition passenger car engines with a CR greater than 14. In this study, a 1.5-liter spark ignition passenger car engine with miller cycle was used to explore the potentials of high CR and methanol direct injection (MDI) on improving engine performances. First, the engine was tested under stoichiometric combustion using methanol and gasoline at BMEPs of 1.1 MPa and 1.5 MPa with CR11.5, CR13.8, and CR15.3. Then, the performances of the CR11.5 case with gasoline and the CR15.3 case with methanol were compared under lean burn combustion. The results show that for gasoline, increasing CR from 11.5 to 15.3 results in decreased fuel economy under stoichiometric combustion, whereas the exact opposite tendency is shown for methanol. Integrating a high CR of 15.3 and MDI improves brake thermal efficiency (BTE) to 43.3 % at an excess air/fuel ratio (λ) of 1.0, when compared with 37.4 % of gasoline at CR11.5. Applying lean burn can further improve the BTE of methanol at CR15.3 to 44.9 %. The main causes of the improvement of BTE by high CR and MDI are the reduced exhaust heat loss resulted from earlier combustion phasing. However, high CR and MDI also extend combustion durations at all specified λs, and emit more THC and CO emissions than low CR with gasoline at high λs because of higher surface/volume ratio and flame quenching. The extended combustion duration and the incomplete combustion are the main barriers to greater BTE for MDI sprak ignition engine with high CR.

Multi-objective parameter optimization for four-stroke single-cylinder diesel engine with soyabean oil blends using NSGA-II

Due to the continuous scarcity of petroleum and related products, there is a greater need for alternative product to petroleum derivatives. The current work investigates the factors influencing the output characteristics of a single-cylinder four-stroke compression ignition engine by utilizing different combinations of blends of soybean biodiesel and fossil diesel, by weight/weight. The experiments have been conducted using the Response Surface Method based on full factorial CCRD and NSGA-II. Mathematical models for BSFC (brake-specific fuel consumption), BTE (brake thermal efficiency), and emission (CO, NOx, and unburned HC) have been proposed using regression equations for optimizing the combustion characteristics (brake-specific fuel consumption), performance characteristics (brake thermal efficiency), and emission parameters (CO, NOx, HC) in NSGA II. A multi-objective optimization problem is created since this investigation aims to minimize BSFC, CO, NOx, and HC and maximize BTE. This research evaluated five optimum combinations of BSFC, BTE, NOx, CO, and HC at variable input factors’ blending ratio and load, and their conformity was checked. It is observed that at a blending ratio of 25.03, the engine performance and emission give better results. At a blending ratio of 25.03% w/w and load 2.08 kW, the brake thermal efficiency is 24.96%, and emission parameters are NOx 52.56 ppm, CO 0.08%, and hydrocarbon 18.11 ppm.

ENGINE PERFORMANCE TEST EVALUATION OF BIODIESEL BLENDS FROM CASTOR SEED OIL AT VARYING MIXTURE RATIOS AND ENGINE SPEED

The growing global demand for energy with expected fossil fuel shortages stresses the search for alternative energy sources. Moreover, the high fossil energy consumption with its adverse impact on environment and climate changes calls for cleaner fuels. One of the most alternative fuel sources is the extraction of biofuels from Castor oil by acid-based catalysed trans- esterification process. In this study, experimental analysis was carried out to produce biodiesel from castor oil using trans- esterification process. The trans- esterification process occurs between castor oil and methanol in the presence of potassium hydroxide (KOH) as a catalyst. The biodiesel fuel produced was varied at different mixture ratios with diesel. The high viscosity and acid value of the castor oil was further reduced by two-three stage trans-esterification process to within the American Society for Testing and Materials (ASTM) D6751 – 0.2 limits for biodiesel. The biodiesel was tested in a single cylinder diesel engine and results of gas emission, load analysis, fuel consumption rate and engine efficiency were all obtained which are close to those of diesel fuel thus confirming that it can be used as alternative fuel for diesel engines. The Brake thermal efficiency was 96% at B-20 biodiesel blend which is close to the conventional diesel engine efficiency of 95.5%.

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.

Investigation into the Ideal Concoction for Performance and Emissions Enhancement of Jatropha Biodiesel-Diesel with CuO Nanoparticles Using Response Surface Methodology.

The present work covers the preparation of biodiesel from jatropha oil through the transesterification process followed by its characterization, and furthermore, performance and emission analyses were done in terms of blending biodiesel with fossil diesel and CuO nanoparticles. Jatropha biodiesel blends (B10, B20, and B30) were chosen for this preliminary investigation based on the observation that B20 outperformed other blends. Next stage B20 with copper oxide (CuO) nanoparticle concentrations of 25, 50, 75, and 50 ppm are used to examine the performance and emission characteristics of a constant speed single cylinder, 4-stroke, 3.5 kW compression ignition (CI) engine. Finally, The response surface methodology (RSM) was utilized to determine the optimal nanoparticle concentration for B20. The results revealed that the blend of B20 with 80 ppm nanoparticles had the highest desirability (0.9732), and the developed RSM model was able to predict engine responses with a mean absolute percentage error (MAPE) of 3.113%. A confirmation test with an error in prediction of less than 5% verified the model's adequacy. When comparing optimized B20CuO80 to diesel, brake specific energy consumption (BSEC) increased by 8.49% and brake thermal efficiency (BTE) was lowered by 3.34%. Hydrocarbon (HC), carbon monoxide (CO), carbon dioxide (CO2), nitrogen oxide (NOx), and smoke emissions were reduced by 3.66% and 2.88%, 4.78%, 22.9%, and 20.54%, respectively, at 80% load. As a result, the B20 blend with nanoparticle concentrations of 80 ppm may be used in current diesel engines without engine modification.

Optimization of CI Engine Performance and Emissions Using Alcohol–Biodiesel Blends: A Regression Analysis Approach

This research paper investigates the optimum engine operating parameters, namely engine load, palm biodiesel, and ethanol percentage, by using a regression analysis approach. The study was conducted on a single-cylinder, four-stroke diesel engine at varying engine loads and constant speed. A general full factorial design was established using Minitab software (Version 17) for three different input factors with their varying levels. The test results based on the regression model are used to optimize the engine load and percentages of palm biodiesel and ethanol in diesel–biodiesel–ethanol ternary blends. The analysis of variance (ANOVA) revealed a significant effect on performance and emission parameters for all three factors at a 95% confidence level. From the regression study, optimum brake thermal efficiency (BTE), nitrogen oxide (NOx), carbon monoxide (CO), and unburnt hydrocarbon (UHC) emissions were found to be 12.57%, 436.2 ppm, 0.03 vol.%, and 79.2 ppm, respectively, at 43.43% engine load, 11.06% palm biodiesel, and 5% ethanol share. The findings of this study can be used to optimize engine performance and emission characteristics. The regression analysis approach presented in this study can be used as a tool for future research on optimizing engine performance and emission parameters.

Experimental investigation of preheated ethyl ester of palm oil for a common rail direct injection diesel engine

The main aim of this research work is to study the performance and exhaust emissions of a common rail direst injection diesel engine at a constant speed of 1500 rpm under load variation by preheating fuels. Fuels are a neat ethyl ester of palm oil (EEPO) and its blended with diesel for the ratios of 10–50% v/v. The fuels are preheated to 65 ± 2 °C and 80 ± 5 °C, respectively. The results of preheated fuels compared with conventional diesel show the changes in performance parameters and exhaust emissions. The preheated neat EEPO resulted in the permutation of performance parameters. The brake thermal efficiency (BTE) reduced while the brake specific energy consumption (BSEC) increased, by 5%. Carbon dioxide (CO2) and nitric oxide (NO) were raised up to 18%, but carbon monoxide (CO) was dropped by 16%. Outstandingly, the preheated conventional diesel mixed with 10% EEPO improved the BTE and the BSEC by 2%. The preheating conventional diesel mixed with increasing EEPO (10–50% v/v) caused the increasing CO2 and NO but the CO emissions were continuously reduced.

Performance analysis of Single-Cylinder CI Engine with Turmeric Leaf Oil Biodiesel at Different Operating Conditions

Biodiesel, made from vegetable oils, non-edible oils, and animal fats, is a promising diesel alternative. The performance of a single-cylinder diesel engine using turmeric leaf oil biodiesel is examined in this study. Three biodiesel blends—B10, B20, and B30—were tested against diesel fuel. The highest brake thermal efficiency (BTE) of 24.84% and the lowest brake-specific fuel consumption (BSFC) of 0.28 kg/kWh were achieved using diesel fuel at 600 bar injection pressure, 18 compression ratio, and full engine load. With the same operating conditions, biodiesel blends B10 (23.84% and 0.29 kg/kWh), B20 (23.38% and 0.32 kg/kWh), and B30 (23.22% and 0.34 kg/kWh) had BTE and BSFC values.

Parametric optimisation and performance evaluation of gasifier-CI engine on dual fuel and dual feed material gasification

Gasification-based energy derived is one of the appealing resources for producing heat and power generation. The objective of this paper is to conduct an experimental study on downdraft air co-gasification of Madhuca longifolia wood and Indian low-grade coal (50:50 wt %) to generate producer gas and its application in dual-fuelled mode CI engine. Besides, the optimisation using the response surface methodology (RSM) has been applied to Gasifier-Engine to determine the best engine performance and emission response by optimising the input variables, i.e. gasifier equivalence ratio, engine compression ratio, and engine load. The RSM-based analysis predicted that optimum input operating parameters could be attained for co-gasification for Equivalence ratio (ER), compression ratio (CR), and engine load (EL) at 0.43, 16, and 100%, respectively. Based on optimal input variables, the performance response values of the gasifier-engine are 29.52% Brake thermal efficiency (BTE), 3.30 kW Brake power (BP), 0.3851 kg/kWh Brake specific fuel consumption (BSFC), 0.0186 vol% CO, 0.958 ppm UHC, 0.9768 vol % CO2, and 109.415 ppm NOx. The results show that the projected regression model has a high accuracy of R2 > 90% and a high correlation coefficient of 0.8927.

Performance and Emission Comparison of Different Test Fuels in a Compression Ignition Engine with Syngas and Pyrolytic Oil Derived from Safflower

ABSTRACT This work aimed to compare the performance and emissions of different test fuels in a compression ignition engine. The fuels included diesel, SFEEE20, and SFME20, with and without a diesel reforming and partial oxidation system. Syngas and pyrolytic oil produced from Safflower were used in single and dual fuel modes. The results showed that brake thermal efficiency (BTE) increased in dual fuel mode compared to single fuel mode. Diesel with SFS exhibited the highest efficiency of 32.20%, followed by SFEEE20 with SFS at 31.91% and SFME20 with SFS at 31.08%. The specific fuel consumption (SFC) decreased in dual fuel, and at maximum load condition, SFME20 with SFS demonstrated the lowest SFC of 0.3193 kg/kW-hr in dual fuel mode. SFEEE20 with and without SFS displayed SFC values of 0.28051 kg/kW-hr and 0.3005 kg/kW-hr, respectively. At maximum load condition, SFME20 with SFS exhibited an EGT of 187°C, while PME and diesel with SFS showed EGT values of 183°C and 184°C, respectively. CO and HC emissions decreased in dual fuel mode compared to single fuel mode. The work concluded that SFEEE20 with SFS showed promising results with high BTE and low emissions, making it a potential fuel blend for compression ignition engines.

Ozone-assisted combustion and emission control in RCCI engines: A comprehensive study

This paper presents an investigation into the combustion and emission characteristics of reactivity-controlled compression ignition (RCCI) engines using ozone seeding, which is known as one of the most highly oxidizing chemical species. The study aims to address challenges pertaining to combustion control and emissions deterioration. Therefore, the current work investigates the RCCI mode of operation in a single-cylinder diesel engine with intake air that has been seeded with ozone by introducing conventional diesel fuel as a high-reactivity fuel using a high-pressure direct injection method and iso-octane as a low reactivity fuel using a low-pressure port injection method. In the experimental study, different ozone concentrations up to 300 ppm and three different energy-based premixed ratios of low reactivity fuel from 0% to 45% with a 15% rise rate were examined under various engine loads and constant engine speed. The methodology used in this research provided for simultaneous decreases in unburned hydrocarbon (HC) emissions and smoke opacity for RCCI engines. According to the experimental findings, simultaneous utilization of RCCI mode and ozone seeding led to a decrease of up to 36% in HC emissions and a reduction of up to 98.7% in smoke opacity. Moreover, nitrogen oxides (NOx) emissions were reduced by up to 39.5% at 20% engine load, whereas carbon monoxide (CO) emissions exhibited a decrease of up to 46% at 60% load. The RCCI mode also yields significant reductions in pollutant emissions and notable increases in brake thermal efficiency (BTE) when compared to the conventional diesel mode (CDM). In conclusion, this experimental study presents a promising solution for addressing emissions deterioration in RCCI engines while simultaneously achieving reductions in pollutant emissions.

Comparative analysis of waste tire pyrolysis oil and gasoline as low reactivity fuel in RCCI engine

ABSTRACT The utilization of alternative fuels in internal combustion engines has gained significant attention due to concerns about energy security and environmental sustainability. Waste tire pyrolysis oil (WTPO) is a potential alternative fuel that can be produced from waste vehicle tires through a pyrolysis process. In this study, the possible use of WTPO in a diesel engine operating under Reactivity Controlled Compression Ignition (RCCI) mode was investigated. In the study, the use of WTPO as a low-reactivity fuel in RCCI engines is examined, highlighting the importance of innovative approaches to alternative fuels with varying reactivity levels for effective combustion control and emission reduction. In the experimental work, WTPO was tested at different energy rates of 15%, 30%, and 45% into the intake port using the PFI system, while conventional diesel fuel was injected directly into the cylinder by the CRDI system. The tests were carried out under different engine load conditions while maintaining a constant engine speed of 2400 rpm. The performance, combustion, and emission characteristics of the engine were analyzed and compared between WTPO and conventional gasoline fuel as LRF. The study results show that using WTPO in RCCI operation with sustainable ringing intensity leads to significant increases in Brake Thermal Efficiency (BTE) compared to gasoline usage, with BTE increments of up to 5%, 3.3%, and 6.3% observed with increasing engine load. Furthermore, WTPO usage in RCCI engines effectively reduced hydrocarbon (HC) emissions, addressing a significant issue, and maintaining the known benefits of reactivity-controlled combustion. These findings suggest that WTPO can be utilized as a viable low-reactivity fuel in RCCI engines with acceptable performance, combustion, and emission characteristics.

Examination of the effect on the engine of diesel-nanoparticle mixture with natural gas addition

Diesel engines have a broader application area and have a significant share in the transportation sector. Although there are restrictions on producing within the scope of emission standards, diesel fuel will remain important in heavy-duty vehicles for some time. Therefore, studies continue for environmentally friendly combustion and low emissions in diesel fuel. This paper reveals the results of using nanoparticle fuel with natural gas (NG) on diesel engine emissions and performance. In the experiments, the motor load was adjusted from no to full load by increasing it at 25% intervals. Three different diesel-nanoparticle blends containing 25 ppm, 50 ppm and 75 ppm carbon nanotube (CNT) were prepared and each of these blends was tested both with and without NG. In light of the test results, it has been seen that the D75ppmCNT + NG mixture is the best fuel mixture compared to both diesel and nanoparticle-added diesel since it provides the highest value in brake thermal efficiency (BTE) and the lowest value in brake specific fuel consumption (BSFC) at full load conditions. In the case of using a D75ppmCNT mixture, around 29% decrease in BSFC and about 28% increase in BTE were observed according to the diesel fuel use. In terms of emissions, when NG is added to the D + CNT fuel mixtures, there is an increment in CO and HC emissions and a slight reduction in NOx emissions at low and medium load.

Experimental investigation of ternary biodiesel blends combustion in a diesel engine to reduce emissions

The study presents an experimental investigation of two new ternary biodiesel blends, namely, ManCr_Pa (a mixture of Mandarin, Crambe biodiesel and paraffin as an additive) and AvBn_Pa (mix of Avocado, Bush nut biodiesel and paraffin) by modifying the critical fuel properties closer to the diesel fuel. Those ternary blends' performance, emission and combustion characteristics were compared with diesel and typical B5 blends at the same engine conditions. The result reveals that at high engine rpm, the new ternary biodiesel blends exhibited nearly similar engine performance to that of diesel fuel with a significant reduction of carbon monoxide (33.3%), hydrocarbons (33.3 to 73.3%) and particulate matter (17.8 to 28.8%). For instance, brake power (BP), brake mean effective pressure (BMEP), and brake thermal efficiency (BTE) slightly decreased by 0.25 to 0.38, 0.27 to 0.42 and 0.04%, respectively, whereas brake specific fuel consumption (BSFC) slightly increased by 0.52%. The ternary blends also demonstrated closer combustion behaviour, i.e. heat release rate (HRR) with diesel at full load conditions. Compared with the typical B5 blend, the modified ternary biodiesel blends showed better engine performance with a substantial reduction of emissions. Interestingly, the ternary blends exhibited lower NOx emissions than the B5 blend. The study concluded that the newly developed ternary biodiesel blends are superior to ordinary B5 blends and closely performing fuel to standard diesel. The results of this study have important implications for using these new blends as substitutes for diesel while realising similar benefits.