Performance and Emission Evaluation of a CRDI Diesel Engine Fueled with Algae Biodiesel and Hydrogen Enrichment

Algae offer an appealing source for creating inexhaustible and feasible biofuels to diesel engine. Researchers evaluated the performance of algae and microalgae biodiesel in various types of diesel engine and reported that engine characteristics of algae biodiesel (B20 blend) are closer to baseline (diesel) fuel but NOX emission is increased for algae and microalgae biodiesel blend in diesel engine. With the purpose to reduce the NOX emission, addition of ignition promoting additive with B20 blend is viable solution without engine modification. In this study, B20 (80% of diesel and 20% algae biodiesel on volume basis) is blended with 5% of di-ethyl ether (DEE), 2-ethylhexyl nitrate (2-EHN) and di-tertiary butyl peroxide (DTBP), namely B20 + 5% DEE, B20 + 5% 2-EHN and B20 + 5% DTBP, respectively, and the impact of the ignition improvers on the engine performance and emission characteristics of biodiesel-fueled diesel engine was examined for the fuel blends. The outcomes demonstrated that the addition of DEE, 2-EHN and DTBP in biodiesel enhanced the performance and emission characteristics of DICI engine and this study concluded that the DTBP can be utilized as promising ignition enhancer for diesel–algae biodiesel blend to compare with DEE and 2-EHN.

Emission and engine performance analysis of a diesel engine using hydrogen enriched pomegranate seed oil biodiesel

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.

Comprehensive evaluation of diesel engine performance can provide an effective guidance for the selection of existing diesel engines and the reasoning, design and evaluation of new diesel engines. In order to scientifically, systematically and objectively evaluate diesel engine performance of armored vehicles, thirteen main performance targets are put forward as comprehensive evaluation targets according to its specific operating requirements, based on an all embracive evaluation of the diesel engine performance. The method of weighted comprehensive evaluation is introduced detailedly and the weights of various targets are determined by comprehensive defined weight. The diesel engine performance of different armored vehicles is evaluated comprehensively using this method. This method is an effective, widely applicable and quantificational method. The example cited proves that this method compares intuitively the advantages and disadvantages in the evaluation of the diesel engine performance of different armored vehicles, with the results obtained valid and dependable. It has definite physical meaning and can indicate comprehensive effect of each performance target of different diesel engines. It provides a new method for quantificationally and comprehensively evaluating diesel engine performance.

The diesel engine combustion process is mainly controlled by the fuel injection characteristics, which will have a direct impact on the performance of the diesel engine, more flexible injection strategy is the development direction of high pressure common-rail system. In order to obtain the change law of the performance of extra-high pressure common-rail diesel engine under variable injection strategy, and improve the overall performance of diesel engine, the effect of different post-injection parameters on the performance of diesel engine was studied on a self-designed extra-high pressure common-rail diesel engine experiment bench, and the relevant results were discussed and analyzed. The results show that: with the rise of post-injection fuel quantity, NOx concentration and soot concentration decrease gradually, and with the rise of post-injection interval angle, NOx concentration decreases gradually, while soot concentration first decreases and then increases. Therefore, choosing post-injection fuel quantity and post-injection interval angle rationally can achieve lower NOx and soot emission at the same time. Meanwhile, with the rise of post-injection fuel quantity or post-injection interval angle, the fuel consumption rate presents an increasing trend.

The hydrogen due to its carbonless structure is considered as a potential supplement fuel in near future for dual-fuel Internal Combustion engines. It reduces the burden of energy imports and reduces carbon containing tailpipe emission, thereby protecting the environment. Hydrogen has inimitable characteristics because of carbonless structure which is considered as better alternative fuel compared to other available options, for example, liquefied petroleum gas, compressed natural gas, etc. In the presented study, investigation was conducted using hydrogen gas in dual-fuel method in single-cylinder CI engine. Hydrogen fuel was inoculated in intake manifold for different injection duration while injecting diesel into combustion chamber directly. The performance of engine is compared with baseline diesel performance at varying injection duration. Experimental observations demonstrated the performance improvement and exhaust emissions using hydrogen enrichment technique. The brake thermal efficiency observed to be improved by 3.17%, and brake specific energy consumption reduces by 10.81% at fully loaded condition for hydrogen gas injection duration of 6 ms as that of baseline diesel performance. Improvement is seen in performance parameters as well as in emissions also, hydrocarbon reduces by 68.18%, and carbon dioxide reduces by 43.33% at full load condition with same injection duration of 6 ms. It was experiential that due to homogeneous mixing of hydrogen with air leads to complete combustion of fuels with lesser emissions. The current study proved that hydrogen enrichment is a potential technology which could be used in compression ignition engines to improve performance and lessening emissions without any major modification in hardware of basic diesel engine.

In the present study, steam injection method (SIM) is implemented to a hydrogen-enriched diesel engine in order to improve the levels of performance and NO emissions. As hydrogen enrichment method increases effective efficiency, NO emissions could be increased. However, the SIM is used to control NO emissions and improve the engine performance. Due to these positive effects, hydrogen enrichment and the SIM)are applied into a diesel engine by using a two-zone combustion model for30% hydrogen enrichment of the fuel volume and 20% steam ratio of the fuel mass at full load conditions. The results obtained are compared with conventional diesel engine (D), steam injected diesel engine (D+S20), hydrogen-enriched diesel engine (D+H30) and hydrogen-enriched diesel engine with steam injection (D+H30+S20) in terms of performance and NO emissions. In the results, the effective efficiency and effective power improve up to 22.8% and %3.1, as NO emissions decrease up to 22.1%. Hence, the hydrogen enrichment with steam injection method is more environmentally friendly with better performance.

The low cost and wide availability of used cooking oil make it a desirable feedstock for the generation of biodiesel. In this study, Three distinct hydrogen enrichment values (4 lit/min, 6 lit/min, and 8 lit/min) and nanoparticle concentrations of 50, 100, and 150 PPM) are combined with used cooking oil blends (10%, 15%, and 20%) to evaluate the CRDI single-cylinder diesel engine's efficiency and emission properties. Split injection technique was used in the experiments to investigate the impact on emissions and engine efficiency. The outcomes reveal a significant improvement in brake thermal efficiency over standard diesel fuel, up to 8%. In addition, a noteworthy decrease was noted in particular fuel consumption and emissions parameters, including smoke, hydrocarbons (HC), and carbon monoxide (CO), under all experimental setups. On the other hand, there was a minor rise in nitrogen oxide (NOx) emissions. With encouraging gains in performance and emissions characteristics, this study clarifies the feasibility of using used cooking oil blends with hydrogen nanoparticle enrichment as a sustainable alternative fuel for CRDI diesel engines. Increased environmental friendliness and overall efficiency could be achieved with this alternative fuel technology with additional refinement and optimisation of engine operating parameters.

To maximize the performance of the diesel engine run with alternative renewable fuels, operational parameters such as injection time (IT) and injection pressure (IP) must be fine-tuned. Meanwhile, hydrogen has come out as a one of the best alternative fuel for dual-fuel mode of operation, since it minimizes the drawback that use of biodiesel alone possesses like low calorific value, high viscosity etc. Based on the above findings, the objective of the current study is set as “to evaluate the impact of varying injection parameters on the engine characteristics of hydrogen-enriched palm fueled CRDI diesel engine.” In this research work, a hydrogen-enriched (7 lpm and 10 lpm) palm biodiesel blend (P20) with diesel fuel was used to examine how changing injection pressure (IP) and injection time (IT) affected CRDI diesel engine performance, combustion, and emission characteristics. Three different IPs (240 bar, 420 bar, and 600 bar) and ITs (23°CA bTDC, 25°CA bTDC, and 27°CA bTDC) are used at a steady speed of 1500 rpm under full load circumstances. The results showed a maximum BTE of 31.09% for P20 + 10 H2 at 25°CA bTDC IT and 600 bar IP. Better fuel atomization is responsible for the improvement in BTE (17.94%) and BSFC (15.15%) with increased IP (600 bar). Advancement in IT (25°CA bTDC) leads to superior performance in terms of HC (32%) and CO (8.33%) emissions reduction for P20 + 10 H2 because more time is available for optimal air-fuel mixing. However, NOX emission increases significantly because of the rise in temperature within the cylinder with hydrogen enrichment. This can be attributed to the high calorific value of hydrogen which is almost three times to that of diesel. A maximum increase in NOX emission of 45.65% is obtained for P20 + 10 H2 w.r.t. diesel. With an increase in IP, ICP and HRR improve by 28.04% and 22.70%, respectively, due to improved fuel atomization, resulting in the greatest amount of fuel being burned during the pre-mixed combustion stage. It can be concluded that the 25°CA bTDC IT and 600 bar IP is the optimum condition when the engine performs at its peak.

A comparative study on NH3/H2 and NH3/CH3OH combustion and emission in an optical SI engine

In the growing energy demand, the use of alternate fuels plays a major role for significant improvements in the emission characteristics and performance of diesel engines. This paper proposed the usage of additives to biodiesel blends combined with thermal barrier coating on the piston crown that will lead to better performance and emission characteristics of diesel engines. From results obtained through various experiments it was determined that the B30 biodiesel blend is the most optimum blend as it has performance characteristics comparable to that of conventional diesel and emissions lower than conventional diesel. The thermal coating of the piston crown encourages better combustion efficiency. The effect of the additives in the fuel blends have led to the decrease of CO, smoke and unburned hydrocarbons emissions. The thermal barrier coating causes the improvement of combustion efficiency in the engine. The performance of the engine is found better with conventional diesel than any biodiesel blends, however the addition of oxygenated additives to the biodiesel blends enables the biodiesel blend to perform in par with conventional diesel.

During the takeoff phase, aircraft engines reach maximum speed and temperature to achieve the required thrust. Due to these harsh operating conditions, the performance of aircraft engines may decrease. This decrease in performance increases both fuel consumption and environmental damage. Reducing or eliminating the damages caused by aircraft is among the objectives of ICAO. In order to achieve this goal, aircraft engines are compulsorily tested, evaluated by experts and certified. The data obtained during the test process is recorded and stored in the engine emission databank (EEDB). During the takeoff phase, there is no system that can evaluate aircraft engines without dismantling and without expert knowledge. In this study, EEDB 2019 and 2021 takeoff phase data sets were used. Fuel flow T/O parameter is an important parameter used both in the calculation of aircraft emissions and in the evaluation of engine performance. Gaussian process regression (GPR), support vector machine (SVM) and multilayer perceptron (MLP) models were used to estimate the fuel flow T/O parameter. The results obtained were compared according to error performance criteria and the best model was selected. In MATLAB® environment, confidence intervals were plotted with the estimated fuel flow T/O value at 99% confidence level. This study demonstrates that the performance evaluation of aircraft engines during the takeoff phase can be performed without the need for expert knowledge.

This paper presents a study on the effect of fuel properties of cottonseed oil biodiesel on the performance of a diesel engine. The fuel properties of a biodiesel determine its effect on the performance of a diesel engine and perhaps, the degree at which it could be considered as a good alternative to the conventional diesel (petro-diesel). In this study, three biodiesel samples were produced from cottonseed oil via transesterification process using three different catalysts (NaOH, CaO, and Nano-CaO), i. e. using single catalyst per sample. The biodiesel samples (denoted by B-NaOH, B-CaO and B-Nano-CaO) were characterized and found to have some differences in their fuel properties. The biodiesel samples (100%) and petro-diesel (for comparison) were tested on a single cylinder Viking Super 165F diesel engine to determine the effects of their properties on performance of the engine. The test results showed that the biodiesel samples gave higher brake thermal efficiencies and higher brake specific fuel consumption compared to petro-diesel at virtually all loads. The results also indicate that B-NaOH biodiesel sample has the highest brake thermal efficiency and lowest brake specific fuel consumption among the biodiesel samples tested. Keywords—Biodiesel, Catalysts, Cottonseed oil, Diesel Engine, Fuel properties, Transesterification.

The object of research is the process of operation of marine diesel engines using biodiesel fuel. The subject of research is the process of experimental determination of the optimal concentration of biodiesel fuel in a mixture with fuel of petroleum origin. At the same time, a simultaneous maximum increase in environmental and minimum decrease in the economic parameters of the operation of a marine diesel engine should be ensured. The studies were carried out on Hyundai Heavy Industries 5H17/28 marine diesel engines. Three such diesel engines were part of the power plant of a specialized marine ship with deadweight of 9600 tons. The study was aimed at determining the concentration of biofuel in a mixture with diesel fuel, which provides the best environmental performance of a diesel engine. The fuel supply circuit to the first diesel did not change and the diesel was operated on RMB30 fuel. Two other diesel engines were operated on a fuel mixture – RMB30 fuel and B99.9 FAME biofuel. The content of biofuel in the mixture varied in the range of 5–20 %. The main quantities measured during the experiment were the concentration of nitrogen oxides and the volumetric content of carbon monoxide in the exhaust gases, as well as the specific effective fuel consumption. By switching groups of consumers, the operation of diesel engines was carried out at the same load, the support of which was required during the experiment. The load on diesel engines during the experiments varied in the range of 55–85 % of the nominal value. The operation of diesel engines in each of the studied modes was carried out for at least 1.5–2 hours, during which the main parameters were measured and the obtained values were averaged. It has been established that the use of biofuel increases the environmental friendliness of the marine diesel engine: – by 7.6–26.61 % (depending on the diesel loading and the content of biofuel in the fuel mixture), the emission of nitrogen oxides with exhaust gases is reduced; – by 3.8–23.6 % (depending on diesel loading and biofuel content in the fuel mixture) reduces the emission of carbon oxides with exhaust gases. It has been also determined that when using biofuel, there is an increase in the specific effective fuel consumption by 0.5–8.65 %, which reduces the efficiency of a diesel engine. The optimal composition of the fuel mixture containing biofuel is proposed to be determined experimentally for each diesel load, taking into account its environmental and economic indicators.

Evaluation of engine performance and emission with methyl ester of Karanja oil