Brake Thermal Efficiency Research Articles

Enhancing ammonia decomposition in ammonium hydroxide/diesel emulsion through hybrid nanocomposite and optimization for improved and greener combustion

In this study, a hybrid nanocomposite was synthesized and characterized to intensify ammonia decomposition in ammonium hydroxide (AH) emulsified diesel fuel. The optimal concentrations of AH and zinc oxide/carbon nanotube (ZnO/CNT) nanocomposite in diesel fuel were evaluated using response surface methodology for effectual and greener combustion. The range of AH concentration was varied from 10 % to 30 %, and ZnO/CNT nanocomposite concentration ranged from 50 ppm to 150 ppm in diesel fuel. Validation experiments were performed to confirm the optimized parameters’ competence compared to regular diesel fuel (RDF). Fourier Transform Infrared and X-ray Diffraction analyses verified successful ZnO/CNT nanocomposite synthesis with desired structural and chemical properties. Optimization results indicated that an 17.2 % volume concentration of AH and 82.3 ppm of ZnO/CNT nanocomposite in RDF yielded efficient combustion with reduced emissions. Validation results showed that the inclusion of 17 % AH in RDF decreased engine brake thermal efficiency (BTE) by 11.1 % and increased brake specific fuel consumption (BSFC), hydrocarbon (HC), carbon monoxide (CO), and oxides of nitrogen (NOx) emissions by 11.3 %, 9.1 %, 9.9 %, and 3 %, respectively. Furthermore, the presence of the nanocomposite (82.3 ppm) enhanced BTE by 10.1 % and reduced BSFC, HC, CO, and NOx emissions by 6.9 %, 6.2 %, 6.9 %, and 5.9 %, respectively. The advancements in fuel additives, such as ZnO/CNT nanocomposites in AH emulsified diesel fuel, have the potential to create more fuel-efficient and cleaner diesel engines. These improvements can significantly contribute to sustainable energy solutions.

Optimizing diesel engine performance and emissions with diesel-hydrogen mixtures: Impact of injector configuration, angle, and pressure

Several factors affect engine performance, including fuel injection pressure, injection angle, and injector orifice diameter. Any deviation from normal conditions in any of these aspects can disrupt optimal engine performance, resulting in inefficient combustion and increased exhaust emissions. To investigate the effect of injector hole number, injection hole angle, and injection pressure on the performance and emissions of a diesel engine operating on a diesel/hydrogen blend (10 % hydrogen and 90 % diesel), a single-cylinder direct injection diesel engine was used. Three injector nozzle configurations just for diesel injector with different hole diameters (0.6, 0.3, and 0.2 mm) were used at injection angles of 0, 15, and 30 degrees, respectively. Three injection pressures (200, 400, and 600 bar) were tested, with results monitored for brake-specific fuel consumption (BSFC), brake thermal efficiency (BTE), smoke, and NOx emissions.Optimal results were achieved with a maximum injection pressure of 400 bar and a nozzle angle of 15 degrees, resulting in improved engine performance and BTE, along with a 6.5 % reduction in BSFC. Increasing the number of injector holes, injection pressure, and injection angle resulted in reduced BSFC and smoke emissions, but with a significant increase in NOx emissions. Notably, this study deviates from traditional combustion methods by introducing air from a 1.1-atmosphere tank instead of relying solely on natural intake. In addition, hydrogen fuel is introduced into the air manifold via a separate injector with an injection pressure of 20 bar, while diesel fuel is injected directly into the combustion chamber.

Enhancing diesel engine performance and emission reduction through hydrogen enrichment in algal biodiesel blends.

The introduction of hydrogen into the engine could enhance its combustion efficiency and emission characteristics. The current study examines the attributes of compression ignition (CI) engines by introducing hydrogen into a biodiesel blend derived from algae. The improved thermal properties of hydrogen, when combined with algae biodiesel, significantly affect the performance, combustion, and emissions of dual-fuel engines. A study was conducted to evaluate the impact of hydrogen enrichment levels of 5%, 10%, 15%, and 20% of the nozzle volume on a biodiesel blend fuel. In comparison to diesel, algal biodiesel reduces emissions of unburned hydrocarbons (HC), carbon monoxide (CO), and oxygen (O2) by 5.19%, 3.61%, and 2.83%, respectively, while increasing nitrogen oxide (NO) emissions by 4.73%. In contrast to biodiesel, diesel demonstrated superior brake thermal efficiency (BTE) and lower specific energy consumption (SEC). Injecting hydrogen into A20 blend fuel at volumes of 5%, 10%, 15%, and 20% results in a respective increase in brake thermal efficiency of 2.65%, 2.97%, 3.50%, and 4.15%. The addition of hydrogen gas to biodiesel blends further enhances their combustion qualities, leading to elevated peak cylinder pressure, temperature, and heat release rate. The results indicate that A20H5, A20H10, A20H15, and A20H20 fuel reduced CO emissions by 3.75%, 8.75%, 12.5%, and 16.25%, respectively, compared to the A20 blend. In the same vein, HC emissions decreased by 5.76%, 10.29%, 15.52%, and 18.98%, respectively, as compared to A20 fuel. However, NO emissions rose by 5.36%, 10.20%, 15.28%, and 23.23%, respectively, for A20H5, A20H10, A20H15, and A20H20 test fuels. Ultimately, the utilization of algal biodiesel and hydrogen enrichment in diesel engines was proven to substantially reduce pollutants while increasing efficiency. This study contributes valuable insights into the intersection of renewable fuels, hydrogen enrichment, and engine technology, with the potential to drive significant advancements in sustainable transportation and environmental conservation.

Effect of injection strategy on the hydrogen mixture distribution and combustion of the hydrogen-fueled engine with passive pre-chamber ignition under lean burn condition

Turbulent jet ignition (TJI) effectively achieves lean and stable combustion in hydrogen engines. However, research on injection strategies for TJI hydrogen engines is still lacking. In this study, experimental methods investigated the effects of single and split injection strategies on the combustion and emissions of TJI hydrogen engines under medium loads. The numerical simulation reveals the operational characteristics of fuel distribution, ignition capability, and energy conversion in the pre-chamber at different injection times in a single injection strategy. This work is conducted at 1600 rpm with a manifold absolute pressure of 70 kPa. The experimental results indicate that the delay of the start of injection (SOI) can enhance the performance of the TJI hydrogen engine. However, as SOI approaches TDC, emissions worsen, and combustion stability decreases. When SOI is 90°CA BTDC, the brake mean effective pressure (BMEP) and brake thermal efficiency (BTE) can achieve 3.1 bar and 32.9 %, with the coefficient of variation of the IMEP (COVIMEP) of 1.6 % and lower emissions. For the split injection strategy, delaying the secondary end of injection (SEOI) can increase BMEP and BTE. As SEOI gradually delays the TDC, emissions deteriorate sharply. Under the split injection strategy, COVIMEP is higher, which is unfavorable for hydrogen engine applications.

Photocatalytic and eco-emission applications of green synthesized ZnO-CB nanoparticles

Herein, we report the synthesis of ZnO nanoparticles (ZnO-CB NPs) by employing the solution combustion method using an aqueous extract of brinjal calyxes as fuel. Characterization techniques, such as X-ray diffraction (XRD), Fourier transform Infrared spectroscopy (FTIR), UV–visible spectroscopy, and Scanning electron microscopy (SEM), were used to investigate the structural, optical, and morphological properties of synthesized nanoparticles, respectively. Highly porous hexagonal crystalline ZnO-CB NPs with less than 7 nm particle size were obtained. The photocatalytic performance of synthesized material is measured with Malachite green (MG), Basic brown 1 (BB1), and Acid orange 36 (AO36) as benchmark dyes. It showed that the synthesized material worked effectively under pH 10 with UV light irradiation. The synthesized ZnO-CB NP shows good removal effectiveness of the MG, BB1, and AO36 dyes with 99.3 %, 99.6 %, and 99.5 %, respectively, which can be promising photocatalysts for ecological applications such as wastewater remediation. Further, the synthesized ZnO-CB NP was used as blends in the methyl ester of Millettia pinnata oil (MPME), which is blended 20 % with commercial diesel (MPME20). The synthesized ZnO-CB NP was added to the MPME20 in varying amounts to ascertain its effects on the quality of emissions of various greenhouse gases such as hydrocarbons, COx, and NOx. Moreover, brake thermal efficiency (BTHE) and brake-specific fuel consumption (BSFC) were studied for the blends. The blend MPME20 with 25 mg of ZnO-CB NP, i.e., MPME20-25 mg, ZnO-CB, displays the best performance and reduced emissions.

Optimization of CRDI engine operating parameters using response surface methodology utilizing lemon peel oil biofuel enriched with hydroxy gas

The current study aims to optimize the operational variables of a CRDI engine in Dual-Fuel Mode (DFM). Hydroxy gas (HHO) was generated through water electrolysis using a concentric four-cylinder dry cell electrolyzer with NaOH catalyst, and it was introduced into the inlet manifold as the primary fuel. The pilot fuel consisted of Lemon Peel Oil (LPO) and pure diesel directly injected into the cylinder. An experimental matrix comprising 17 distinct runs was designed using Design of Experiments (DoE), utilizing Box-Behnken Design (BBD) based on Response Surface Methodology (RSM). The RSM model was created depending on the experimental data, and then operating parameters were optimized utilizing the desirability technique. The optimal engine operational variables were identified for the B25 LPO mixture with a constant HHO gas flow rate of 0.5 LPM, a Compression Ratio (CR) of 21.5, an Injection Pressure (IT) of 450 bars, and an inlet air temperature of 87℃. The optimized results were 30.18 % for Brake Thermal Efficiency (BTE), 9.532 g/kW-hr for Carbon Monoxide (CO) emission, 0.253 g/kW-hr for Unburned Hydrocarbon (UHC) emission, and 23.510 g/kW-hr and Nitrogen Oxides (NOx) emission, yielding a total desirability of 0.7641. Empirical validation of the optimized responses at these input conditions demonstrated their conformity to acceptable error ranges.

Modeling the impact of plastic oil obtained from xlpe cable wastes on diesel engine performance and combustion parameters with the response surface method

The world's expanding population requires alternative energy sources to meet its energy needs. One such alternative is the efficient recovery of plastic waste through pyrolysis. The liquid produced from waste plastics via pyrolysis is a valuable commodity that may serve as fuel substituted for internal combustion engines. In this study, waste plastic oil (WPO) and diesel fuel (D100) blends (10%, 20%, 30%, 40% and 50% by volume) obtained by pyrolysis of waste XLPE cables were experimentally investigated and analyzed using response surface methodology (RSM) to determine their effects on the combustion parameters of a four-stroke, single cylinder diesel engine at different engine loads (750, 1500, 2250, 3000, 3750 and 4500 W). A response surface model was constructed using a two-factor central composite complete design and analysis of variance based on the experimental results obtained. The model determined the optimum values of WPO ratio and engine load that correspond to one of the finest brake thermal efficiency (BTE), brake specific fuel consumption (BSFC), hydrocarbon (HC), carbon monoxide (CO), nitrogen oxides (NOx), and smoke emission levels. The study's optimization findings indicated that the optimal WPO ratio is 19.6%, and the optimal engine load is 2600 W. The BTE, BSFC, CO, HC, NOx, and smoke were found to be 22.3%, 332.3 g/kWh, 0.033%, 31.5 ppm, 397.9 ppm, and 1.63%, respectively, at the optimal WPO ratio and engine load. The R2 (correlation coefficient) values for BTE, BSFC, CO, HC, NOx, and smoke emissions were determined to be 99.95%, 97.76%, 98.10%, 99.74%, 99.74%, 99.79%, and 95.67%, respectively. The mean error rates, ranging from 0.64% to 4.27%, were deemed satisfactory when comparing the replies to the experimental data. The findings of this study demonstrated that the response surface method is a very efficient approach for forecasting and enhancing a diesel engine's performance and emission characteristics by using waste plastic oil.

Predict the characteristics of the DI engine with various injection timings by Glycine max oil biofuel using artificial neural networks.

Glycine max oil biofuel (GMOB) is a product of the transesterification of soybean oil. It contains a substantial amount of thermal energy. In this study, the result of varying fuel injection timings on the performance, ignition, and exhaust parameters of a research engine with single-cylinder, four-stroke with direct injection (DI) diesel was experimentally investigated and optimised using artificial neural networks (ANN). The results demonstrated that a 20% fuel blend with 24.5° before top dead centre (b TDC) decreased brake thermal efficiency (BTE), NOx emissions, and exhaust cylinder temperature but improved fuel consumption, carbon dioxide emissions (CDE), and smoke emissions. With 26.5° b TDC, the BTE was found to be approximately 5.0% higher while the fuel consumption was approximately 2.0% lower than with the original injection timing of 24.5° b TDC. At 26.5° b TDC, the NOx emission was approximately 8.6% higher, and the smoke emission was approximately 4.07% lower than at the original injection timing (24.5° b TDC).

Environmental Exhaust Emissions reduction and Performance Improvement Analysis of biodiesel operated Diesel Engine Performance Using Operating Parameters

<p style="margin-top:3px; margin-bottom:3px; text-align:justify; text-indent:31.5pt">The present investigation aims to study the performance and emission characteristics of a CI DI diesel engine using biodiesel blends derived from Jatropha seed feedstock. Four blends, namely B25, B50, B75, and B100, are employed as fuels to run the diesel engine at a rated speed of 1500 rpm, and their performance and emission characteristics are determined under different operating conditions in the first phase. The blend B25 of JME is found to be the optimum blend, and the optimum compression ratio is found to be 18.5.The optimum blend exhibits better performance in terms of brake specific fuel consumption (BSFC) and brake thermal efficiency (BTHE), along with a decline in the emissions of carbon monoxide (CO) and hydrocarbons (HC), except for the emission of nitrogen oxides (NOX) at the optimum compression ratio of 18.5. At maximum load, with a compression ratio of 18.5, the optimum blend results in better BSFC and BTHE, which are 0.255 kg/kW-hr and 31.87%, respectively.</p>

Experimental investigation and optimization of performance, emission, and vibro-acoustic parameters of SI engine fueled with n-propanol and gasoline blends using ANN-GA coupled with NSGA3-modified TOPSIS hybrid approach

In the present study, performance, emission, and vibro-acoustic studies were conducted on a spark ignition (SI) engine fueled with gasoline and an n-propanol blend at variable compression ratio (CR), speed, and propanol blend fraction (PBF). Experimental data were used to model an artificial neural network (ANN) trained with a genetic algorithm (GA). ANN predictive responses were employed to establish regression relationships between brake power (BP), brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), oxides of nitrogen (NOx), carbon monoxide (CO), hydrocarbon (HC), resultant vibration acceleration (RVA), and sound pressure level (SPL) with operating parameters using response surface methodology (RSM). These models served as objective functions in the non-dominated sorting genetic algorithm-3 (NSGA3), a multi-objective optimization (MOO) technique, to optimize responses and obtain non-dominated solutions. These solutions were filtered using a modified technique for order preference by similarity to the ideal solution (TOPSIS) to obtain a compromised optimal solution. ANN-GA model outcomes showed high accuracy, with coefficient of determination (R2) and root mean square error (RMSE) values ranging from 0.979 to 0.993 and 0.0381 to 0.0643, respectively. NSGA3 coupled with modified TOPSIS identified optimal operating conditions at 1271.77 RPM, a CR of 11.96, and a PBF of 33.26 %.

Optimization on manifold injection in DI diesel engine fuelled with acetylene

Researchers demonstrated that implementing new combustion technology and optimising fuel quantity results in a significant reduction in traditional fossil fuel usage and emission levels. The Reactivity Controlled Compression Ignition (RCCI) combustion strategy is one of the low temperature combustion technologies, and it is used to reduce the overall combustion temperature while also providing better combustion control. This study looks into RCCI combustion technology, which uses conventional diesel fuel as the high reactivity fuel (HRF) injected through the injector and acetylene gas as the low reactivity fuel (LRF) injected into the cylinder via a modified inlet manifold alongside air. The modified engine setup was tested for performance, emissions, and combustion under various load conditions, as well as different mass flow rates of acetylene gas, a low reactivity fuel that is injected with air. The flow field of the low reactivity fuel at the inlet manifold is analysed using the Computational Fluid Dynamics principle, which is used to determine the best flow rate for improving combustion quality. According to the simulation results, the optimal acetylene flow rate is 3 Litres Per Minute (LPM), and experimentation shows that at 3 LPM acetylene injection, the brake thermal efficiency (BTE) improves by about 3.2%, and emissions such as carbon monoxide (CO), hydrocarbon (HC), smoke intensity, and oxides of nitrogen (NOx) are reduced by about 35%, 17%, 10%, and 21%, respectively.

Split injection timing optimization in ammonia/biodiesel powered by RCCI engine

Employing carbon-neutral (NH3) and low carbon footprint (biodiesel) fuels in Reactivity Controlled Compression Ignition (RCCI) engine mode is one possible method for minimizing carbon emissions in diesel engines. In this study, a Compression Ignition (CI) engine was customized to run in RCCI mode, employing High Reactive Fuel (HRF) as biodiesel and Low Reactive Fuel (LRF) as ammonia (NH3). Based on our earlier findings, the proportion of ammonia in premixing is fixed at 40 %. In the first phase, the primary injection timing of the algal biodiesel varied between 12 and 21°CA bTDC at a preset pre-injection timing of 46°CA bTDC. In the next phase, the pre-injection time varied between 46 and 54°CA bTDC, with the optimal main injection time being 18°CA. The result suggested that the optimal main and pre-injection at 18 and 58°CA bTDC increased the Cylinder Pressure (CP) by 30.1 %, and peak HRR and combustion phase angle were advanced. Brake Thermal Efficiency exhibited an 11 % enhancement, with Brake Specific Energy Consumption decreasing by 24.1 %. Nitrogen Oxide levels saw an increase of around 39.5 %. In contrast, reductions of 19.2 %, 23.5 %, 39.7 %, and 21.7 % were observed in Hydrocarbons, Carbon Monoxide, smoke emissions, and Exhaust Gas Temperature, respectively, compared to the single injection under full load conditions.

Evaluation of ethanol-gasoline blends in SI engines using experimental and ANN techniques

Fuel combustion has become a major global concern, with much research focusing on the various emissions resulting from different types of fuels. Due to the harmful pollutant emissions from fossil fuels, the world has turned to renewable and alternative fuels to limit toxic emissions and greenhouse effects. Ethanol is a biofuel that, when used in spark ignition engines with gasoline can improve the octane number, combustion efficiency, and produce less emissions. The current research studies the effect of different ethanol blends E0, E5, E10, and E15 with gasoline 92 on engine performance parameters and emissions of a GX35 four-stroke engine at different engine speeds. The results along the speed range reveal that increasing ethanol amount leads to an average increase of 2.7%, 1%, and 1.1% in brake power (BP), brake thermal efficiency (BTE), and CO2 emissions, respectively. Meanwhile, it causes an average decrease of 28 °C, 3%, 15 ppm, and 0.18% in exhaust gas temperature (EGT), brake-specific fuel consumption (BSFC), HC, and CO emissions respectively. Moreover, the current study develops an Artificial Neural Networks (ANN) model for predicting the performance and emissions of spark ignition (SI) engines. Python programming language is used for ANN coding to train and validate the ANN model with E15. Regression plots were generated to visualize the correlation between the target and predicted data, indicating outstanding performance. The results confirmed the model’s reliability for BP, EGT, CO, CO2, and HC parameters with R2 values more than 0.99 and with acceptable performance for BSFC and BTE with R2 of 0.9339, and 0.9708, respectively. To ensure that the is no overfitting during the ANN study, we used different statistical methods, such as validation set, cross-validation, and learning curves.

Research on the performance of methanol/PODE dual fuel spark-assisted compression ignition combustion with different intake air adjustment

There is room for continued research and optimization on the exothermal processes and performance of methanol/polyoxymethylene dimethyl ether (PODE) dual fuel spark-assisted compression ignition (DF-SACI) with different air adjustment. The exothermal processes of methanol/PODE DF-SACI were investigated and optimized at varying methanol premix ratios (RM) and intake adjustment methods to maximize the promoting effect of spark ignition (SI). The results show that burning intensity progressively falls, while the ignition delay, CA50 and combustion duration progressively rise as excess air coefficient (λ) climbs. The resistance of high RM to lean combustion is weaker than low RM. As λ grows, the high-intensity exotherm is progressively transformed to the softer exotherm. Consequently, the exothermal energy from premixed compression ignition is progressively converted into the exothermal energy from DF-SACI. Subsequently, the exothermal energy from DF-SACI is progressively replaced by the exothermal energy of diffusion and SI combustion. By reducing air through intake variable valve timing (VVT), the optimal brake thermal efficiency (BTE) and RM under brake mean effective pressure (BMEP) of 0.4 MPa can be elevated to 40.67 % and 60 %, respectively. The optimal BTE for BMEP of 0.6 and 0.4 MPa are further enlarged from 42.82 % and 40.67 % to 43.52 % and 41.41 % by adjusting exhaust VVT, respectively.

Response Surface Optimization of Brake Thermal Efficiency and Specific Fuel Consumption of Spark-Ignition Engine Fueled with Gasoline–Pyrooil and Gasoline–Pyrooil–Ethanol Blends

<div>The present study explores the performance of high-density polyethylene (HDPE) pyrooil and ethanol blends with gasoline in SI engine using statistical modeling and analysis using response surface methodology (RSM) and the Anderson–Darling (AD) residual test. The pyrooil was extracted from HDPE through pyrolysis at 450°C and then distilled to separate the liquid fraction. Two blends were prepared by combining pyrooil and gasoline, and pyrooil–ethanol mixture (volume ratio of 9:1) and gasoline, both at volumetric concentrations ranging from 2% to 8% to evaluate brake thermal efficiency (BTE) and specific fuel consumption (SFC) in a SI engine. An experimental matrix containing speed, torque, and blend ratio as independent variables for both blends were designed, analyzed, and optimized using the RSM. The results show that a 4% blend of pyrooil with gasoline (P4) and a 6% blend of pyrooil–ethanol mixture with gasoline (P6E) were optimum for an SI engine. Also, the experimental findings show that the P6E blend exhibits 11% higher BTE and 11.82% lower SFC compared to base fuel (pure gasoline), and 7.55% higher BTE and 6% lower SFC than P4. From the AD test, the residuals for BTE and SFC follow a normal distribution. The results conclude that distilled HDPE pyrooil could be used in SI engines at concentrations of P4 and P6E without requiring engine modification.</div>

The combustion and emission characteristics of pure methanol as a substitute fuel for compression ignition engines

ABSTRACT Methanol, as a carbon-neutral resource, exhibits significant potential in the automotive sector. The objectives of this study are to investigate the fuel economy, emission characteristics, and combustion properties of methanol in compression-ignition engines. The research findings indicated that the combustion duration of methanol significantly extended with increasing speed and load. In comparison to diesel, methanol exhibited a relatively lower peak heat release rate under various operating conditions. With an increase in injection pressure or an advancement in injection timing, the brake specific fuel consumption (BSFC) decreased initially and then increased. The optimal injection pressure for methanol was lower than that for diesel, while the optimal injection timing was advanced. As the EGR rate increased, BSFC gradually decreased at each speed. When comparing optimized methanol with diesel, the brake thermal efficiency (BTE) of methanol was 37.54%, slightly lower than that of diesel. Methanol’s NOx, soot, and CO emissions were significantly lower than diesel, while methanol and formaldehyde emissions were higher, especially with a methanol emission of 0.83 g/kW.h. Overall, applying pure methanol as fuel in compression-ignition engines can significantly reduce emissions while maintaining the BTE as compared with that of diesel fuel, but the methanol emissions in the exhaust increase significantly.

Study on the integration of hydrogen in a multi-cylinder low heat rejection diesel engine using a ternary blend

Among alternative fuels, hydrogen (H2) holds significant promise as both a fuel and an energy carrier. It is expected to become a key alternative fuel in the near future to meet stringent pollution standards. H2 is used in internal combustion (IC) engines, gas turbines, and the aerospace industry due to its non-toxic and odorless nature, high calorific value (CV), and wide temperature range of combustibility. Additionally, it is a long-term renewable energy source that produces fewer pollutants. This study explores the impact of different H2 ratios on combustion behavior, engine performance, and emission characteristics in a dual-fuel compression ignition (CI) diesel engine. The current research focuses on the effect of TB of ethanol, Jatropha methyl ester, and diesel with the induction of H2 with different flow rates in diesel engine in dual fuel mode (DFM). The tests were performed at different engine loads, 25%, 50%, 75%, and 100% at a constant engine speed of 2500 rpm. H2 is inducted at different flow rates like 2, 4, and 6 Litres per minute (lpm). Partially stabilized zirconia (PSZ) is used to coat the cylinder head, piston crown, and valves with a thickness of 0.5 mm. The combined effect of TB fuel and H2 in a CI engine improves combustion and engine performance. At full load condition, brake thermal efficiency (BTE) is improved by 11.5% for TB fuel with H2 at 6 lpm, and exhaust gas temperature (EGT) increased by 12.7%. The cylinder pressure (CP) and heat release rate (HRR) are increased by 7.5% and 10.6% at TB fuel with 6 lpm of H2 induction. The utilization of H2 as an alternative energy source has significant consequences for the future of green energy production.

The conjoint effect of lab-grown nano-graphene dispersant and omega-9 fatty acid surfactant on performance of CI engine

This article aims to assess the performance characteristics of lab-grown graphene nanoparticles via electrolytic exfoliation as nano additives in engine oil. Physical characterization confirmed the morphology and purity of the prepared graphene nanoparticles. Nanolubricants were prepared at 0.1%, 0.2%, and 0.3% volume fraction of the nanoparticles with the addition of oleic acid as surfactant. Measurements of density and viscosity for the nanolubricants were recorded at varying concentrations and temperatures. The performance parameters of a 4-stroke single-cylinder compression ignition (CI) engine were computed using the formulated nanolubricants. The emission of toxic gases into the environment post-engine performance evaluation was also analyzed for different formulations of nanolubricant samples. Results showed that the relative viscosity variation with concentration for the experimental data was in well agreement with other available predictive models. The nanolubricant with 0.1% concentration yielded a reduction of 13.96 ± 0.39% in total fuel consumption (TFC), a reduction of 5.55 ± 0.17% in brake-specific fuel consumption (BSFC) and an augmentation of 3.96 ± 0.13% in brake thermal efficiency (BTE) in comparison to plain engine oil and other prepared formulations. Also, a marginal reduction in emission of exhaust toxic gases i.e., (2.13 ± 0.1%) ppm in NOx and a significant maximum reduction of 7.46 ± 0.2% in smoke opacity has been obtained with 0.1% nanolubricant sample as compared to other test samples. The results from the present study may be useful for developing sustainable nanolubricants for environmental viability and energy savings.

Optimization of Performance, Emissions, and Vibration in a Hydrogen-Diesel Dual-Fuel Engine Using Response Surface Methodology

Background: Dual-fuel diesel engines using hydrogen as a secondary fuel source are a promising technology for reducing emissions while maintaining engine performance. However, optimizing these engines for all three aspects (performance, emissions, and vibration) simultaneously presents a challenge. Objective: This study aimed to address this challenge by employing Response Surface Methodology, a statistical technique used to optimize multi-variable processes. The goal was to find the ideal combination of engine load, hydrogen flow rate, and compression ratio that would maximize Brake Thermal Efficiency while minimizing Brake-Specific Fuel Consumption, Nitrogen Oxide emissions, and engine vibration. Method: A Box-Behnken design, a specific type of design optimization with three factors and three levels, was employed. The experiment evaluated the impact of three key factors: engine load (ranging from 0 - 12 kg), hydrogen flow rate (0-15 L/min), and compression ratio (16 to 18:1). The effects of these factors on performance, emissions, and vibration were measured. Results: The results revealed a trade-off between achieving optimal performance and minimizing emissions. The highest Brake Thermal Efficiency and lowest Brake-Specific Fuel Consumption were achieved at a high compression ratio (18:1), maximum hydrogen flow rate (15 L/min), and under full engine load (12 kg), corresponding to a brake power of 3.5 kW. However, these conditions also resulted in higher NOx emissions and vibration levels. Conversely, minimizing NOx and vibration occurred at a lower compression ratio (16:1), with the same maximum hydrogen flow rate (15 L/min), but at a significantly reduced engine load (3 kg), resulting in a much lower brake power of 0.875 kW. Conclusion: These findings highlight the complex relationship between performance, emissions, and vibration in a hydrogen-diesel dual-fuel engine optimized using Response Surface Methodology. While optimal conditions were identified for specific goals, achieving all desired characteristics simultaneously across the entire operating range remains a challenge.

Effect of addition of biodiesel having Karanja oil on exhaust emissions and performance in a diesel engine with hydrogen as a secondary fuel

With a specific end goal to take care of the worldwide demand for energy, broad research is done to create alternative and cost-effective fuel. The fundamental goal of this examination is to investigate the performance, emissions and vibration characteristics of a single cylinder four stroke diesel engine, working in dual fuel mode with biodiesel of Karanja oil ((BKO) as a renewable fuel and hydrogen (H2) as gaseous fuel on low (2%), intermediate between medium-high (53%) and high (69%) load conditions. Biodiesel of Karanja oil as 20% biodiesel and 80% diesel known as BKO20, while 30% biodiesel and 70% diesel known as BKO30. With 25% introduction of gaseous fuel (H2) and biodiesel (10%–40%) along with diesel showed an increase in brake thermal efficiency (BTE), 85.23%, 10.62% and 19.4% respectively as compared to parent diesel fuel operation. As far as emission is concerned, oxides of nitrogen (NOx) decreased on higher load conditions with a variation of biodiesel (10%–50%) in comparison to low load condition. However, the formation of monoxide (CO), carbon dioxide (CO2) and un-burnt hydrocarbon (HC) decreases along with BKO50 using 25% hydrogen fuel substitution at high (69%) load conditions.