Performance Evaluation Of Engine Research Articles

Data-driven identification for approximate analytical solution of first-passage problem

The first-passage problem plays a significant role in engineering performance evaluation and design optimization. To address general stochastic dynamical systems, a data-driven method is proposed to identify approximate analytical solutions for the first-passage problem which explicitly includes parameters of the system, excitation, and those related to the initial and boundary conditions. The method consists of two successive processes. First, the probability density of the first-passage time is assumed to satisfy the modified Weibull distribution and its expansion expression is constructed by using the rule of dimensional consistency. Second, by comparing the expansion with the probability density of the first-passage time estimated from random state data, the coefficients are determined by solving a set of overdetermined linear algebraic equations. Two representative examples, including the Duffing oscillator and a 2-DOF nonlinear dynamical system, are discussed in detail to illustrate the application and efficiency of the data-driven method. The efficacies of the approximate analytical solutions for the external parameters are also verified.

Numerical investigations on charge motion and combustion of natural gas-enhanced ammonia in marine pre-chamber lean-burn engine with dual-fuel combustion system

Ammonia, an efficient hydrogen carrier with the advantages of lower storage cost and higher stability comparing to hydrogen, is becoming a potential solution for carbon dioxide emission reduction from marine engine. In this paper, the CH4/NH3 mechanism applied to simulate the combustion process of elevated-pressure engine was experimentally verified. Then, simulations were conducted on a marine pre-chamber lean-burn engine to investigate the feasibility of dual-fuel combustion with natural gas and ammonia. The results show that the combustion of the rich mixture ignited by spark in the pre-chamber produces high-speed turbulent jet flames into the main chamber, which promotes the combustion of the lean gas mixture. Additionally, an anomalous pre-ignition pressure rise is observed at 50% natural gas addition. Finally, the performance evaluation of engine indicates that for the design of marine dual-fuel engine, the ammonia fraction range of 50%∼80% should be employed to achieve good engine thermal efficiency.

Дизель қозғалтқыштарының негізгі көрсеткіштеріне аралас отынның әсерін экологиялық бағалау

The article provides a comprehensive analysis of existing types of alternative fuels, including in-depth studies of chemical and physical properties. According to the results of the study, dimethyl ether was selected. When mixing a certain amount of dimethyl alcohol with diesel fuel and using the resulting mixture to evaluate engine performance, a linear regression analysis method was used. Finding the values of linear regression coefficients was carried out using an application software package (MATLAB) to solve technical calculation problems. Studies have shown that the addition of one third of dimethyl ether to diesel fuel is the most effective additive for reducing the residual gases emitted by diesel engines. A decrease in the indicators of residual gases leads to an improvement in environmental indicators.

Trend in tropopause warming and its influence aircraft performance

PurposeTemperature anomalies in the upper troposphere have become a reality as a result of global warming, which has a noticeable impact on aircraft performance. The purpose of this study is to investigate the total air temperature (TAT) anomaly observed during the cruise level and its impact on engine parameter variations.Design/methodology/approachEmpirical methodology is used in this study, and it is based on measurements and observations of anomalous phenomena on the tropopause. The primary data were taken from the Boeing 747-8F's enhanced flight data recorder, which refers to the quantitative method, while the qualitative method is based on a literature review and interviews. The GEnx Integrated Vehicle Health Management system was used for the study's evaluation of engine performance to support the complete range of operational priorities throughout the entire engine lifecycle.FindingsThe study's findings indicate that TAT and SAT anomalies, which occur between 270- and 320-feet flight level, have a substantial impact on aircraft performance at cruise altitude and, as a result, on engine parameters, specifically an increase in fuel consumption and engine exhaust gas temperature values. The TAT and Ram Rise anomalies were the focus of the atmospheric deviations, which were assessed as major departures from the International Civil Aviation Organizations–defined International Standard Atmosphere, which is obvious on a positive tendency and so goes against the norms.Research limitations/implicationsNecessary fixed flight parameters gathered from the aircraft's enhanced airborne flight recorder (EAFR) via Aeronautical Radio Incorporated (ARINC) 664 Part 7 at a certain velocity and altitude interfacing with the diagnostic program direct parameter display (DPD), allow for analysis of aircraft performance in a real-time frame. Thus, processed data transmits to the ground maintenance infrastructure for future evaluation and for proper maintenance solutions.Originality/valueA real-time analysis of aircraft performance is possible using the diagnostic program DPD in conjunction with necessary fixed flight parameters obtained from the aircraft's EAFR via ARINC 664 Part 7 at a specific speed and altitude. Thus, processed data is transmitted to the ground infrastructure for maintenance to be evaluated in the future and to find the best maintenance fixes.

Economic Viability and Engine Performance Evaluation of Biodiesel Derived from Desert Palm Date Seeds

Desert palm date seeds are a potential feedstock for biodiesel and biomass pellet production, particularly in the Middle East and Africa. A model was developed in this study based on optimal conditions for the production of biodiesel, and it was used to evaluate the financial viability of a small-scale biodiesel plant (1000 t/y) using economic performance metrics including net present value, rate of investment, and payback period. Biodiesel was then produced from date seed oil (DSO) and blended with petrol diesel to make four blends (B5, B10, B15, and B20). The technical performance of these blends was investigated using a test engine rig under differing operating conditions, including variations in load and rpm. The investment performance of the proposed biodiesel plant was very sensitive to the price of biomass pellets; the project was feasible only when this was 70% that of wood pellets or higher. The baseline diesel outperformed the biodiesel blends in terms of engine power, thermal efficiency, and fuel economy, with average decreases of 4.5%, 7.65%, and 9.84%, respectively, at full load for B20. However, the biodiesel blends outperformed the baseline diesel in exhaust gas temperature (EGT), with average drops of 29 and 46.7 °C at full load for B5 and B20, respectively. Our study clearly demonstrates that due to it being obtained from existing waste materials, having a cleaner but comparable performance, and its economic viability, date seed oil has excellent potential as a feedstock for biodiesel production.

Research on flame temperature measurement method based on water vapor emission spectrum

Internal temperature monitoring of high-speed propulsion systems is highly important for engine performance evaluation and lifetime prediction. As a passive optical measurement method without the need for an external light source and without flow field interference, the emission spectrum measurement technique has good application prospects for harsh measurement environments. As the main combustion product, high-temperature water vapor shows a strong emission intensity that is highly suitable for temperature measurement applications. We propose use of the band integral ratio to remove the high resolution measurement requirements for the spectrum acquisition system. In addition, the temperatures of methane-oxygen flames with different equivalent ratios are measured successfully under the condition that the influence of self-absorption on the measurements is considered.

Influence of hydrogenated diesel/H2O2 blend fuel on diesel engine performance and exhaust emission characterization

The oxygenated hydro diesel (OHD) is prepared from hydrogen peroxide (H2O2), acetone, and seaweed polysaccharide. A long-term study was carried out on the OHD fuel blend stability for about a year at various temperatures. The long-term stability shows very stable properties, no easy emulsion breaking, and a long storage period. The neat diesel and blend fuel performance test was conducted at various engine speeds, 1700–3100 RPM the diesel blend with 5 wt.% and 10 wt. % of H2O2 revealed the best fraction for reducing smoke and emissions. The blend contains 15 wt.% H2O2, revealing a significant reduction in exhaust temperature without considering the engine's performance. Moreover, the performance of the OHD also revealed an economizing rate, decreasing environmental pollution and prolonging the engine’s service life. The diesel engine performance and environmental evaluation leading to exhaust emissions characterization ({mathrm{CO}}_{mathrm{X}}, {mathrm{SO}}_{mathrm{X}}, {mathrm{NO}}_{mathrm{X}}, and others). Based on the results, the various concentrations of H2O2 are an effective method for reducing the emission of diesel engines. Decreased CO, SO2, unburned hydrocarbons, and NO2 were also observed as percentages of H2O2. Due to increased oxygen content, water content and cetane number, the number of unburned hydrocarbons from diesel fuel decreased with the addition of H2O2. Therefore, the OHD blend can significantly curtail the exhaust emission of conventional diesel fuel, which will help reduce the harmful greenhouse gas emissions from diesel fuel sources.

Performance evaluation of diesel engine with electroless nickel plating on piston skirt

The principle operation of the engine, converts the chemical energy of a fuel into heat energy. The produced heat energy can be utilized for useful works in Industries, Automotives, Agriculture and power production applications. In Internal Combustion engines combustion is a important phenomena to developing the heat energy from the engine cylinder. Due to corrosion, wear and tear on the Piston skirt, the heat energy is not effectively produced inside the cylinder of the engine and a large amount of exhaust gases is released. The piston skirt is coated with Electroless Nickel plating, it improves the combustion rate and efficiency of the engine. The performance results show that it reduces the 19.4% NOx and 8.6% of PM emissions, heat losses and improves the brake power, and corrosion resistance of the piston.

RDE cycle simulation by 0D/1D models to investigate IC engine performance and cylinder-out emissions

In this work, the development and application of advanced predictive 0D/1D methodologies to simulate Real Driving Emission (RDE) cycles are described. Firstly, the 1D simulation model is validated on a map of steady state operating points, which allows to use successively the very same model, with its calibration, during an RDE cycle simulation, considering the sequence of varying loads, and rotational speeds. In particular, the validated 1D model is used to simulate a typical RDE transient cycle of approximately 1 h and 45 min. The test case investigated is a modern plug-in hybrid passenger car engine, in which the thermal power unit consists of a 1 L three-cylinder, turbocharged gasoline engine. The experimental and simulated RDE cycle is characterized by a sensibly varying Internal Combustion Engine (ICE) operation, allowing to evaluate engine performance and cylinder out emissions. To speed up the calculation and significantly lower the Central Processing Unit (CPU)/real time ratio a dedicated numerical solver for fast simulation has been implemented and tested, while keeping the fidelity of the results. A predictive 0D, multi-zone model for Spark Ignition (SI) combustion has been applied, together with emission sub-models for the calculation of the main pollutants. Both instantaneous and cumulative emissions have been evaluated. The results of the simulations have been compared to the experimental data of RDE cycles, showing a good predictiveness of the models and the high potential of 0D/1D simulation codes as design tools, in the new scenario of demanding testing procedures. This approach can be applied for any engine configuration operating under any transient condition.

Optimization of diesel engine performance and emission characteristics with cerium oxide nanoparticles mixed waste cooking oil biodiesel blends

The study investigates the performance and emission characteristics of a four-stroke, single-cylinder, and direct injection diesel engine with variable compression ratio using nanoparticles blended biofuel. The cerium Oxide (CeO2) nanoparticles have been blended in corresponding ratios with waste cooking oil (WCO) biodiesel. Further, response surface methodology (RSM) based Box-Behnken design (BBD) approach was used to evaluate engine performance parameters such as brake specific fuel consumption (BSFC), brake thermal efficiency (BTE), and emission characteristics (such as NOx, CO, and CO2 emission). In addition, the quadratic models were obtained to investigate the influence of input parameters on each output response with analysis of variance (ANOVA). The desirability approach was used to obtain the optimal engine performance and emission characteristics. The analysis revealed that WCO blended with CeO2 nanoparticles fuel improves CI engines’ performance and reduces their hazardous emissions. The compression ratio of 14:1 at 10.29% blend composition and 50 ppm concentration level of nanoparticles with composite desirability of 0.858 was found to be the engine’s optimal operating conditions. At optimal conditions, BTE, BSFC, NOx, CO, and CO2 were 36.62%, 0.2204 kg/kW-h, 168 ppm, 0.0192%, and 1.132% respectively.

Performance and emission evaluation of CI engine fueled with ethanol diesel emulsion using NiZnFe2O4 nanoparticle additive

Diesel engines are widely used due to their higher thermal efficiency and lower Hydrocarbon (HC) emissions. The price fluctuation of petroleum fuel; the none-renewability and different hazardous emissions from petro-diesel, researchers are searching for a suitable renewable energy source for diesel engine. Ethanol is one of the promising alternative fuels that could be used to power diesel engine. Some of the techniques so far tried are ethanol fumigation, dual injection and blending. The former techniques need different engine modification to enable the additional systems to work on the existing engines. Blending is the best technique to substitute the existing diesel fuel as long as we prepare it as per the current diesel fuel minimum requirement. For this specific case micro emulsion of ethanol in diesel fuel with emulsifier is prepared by using magnetic stirrer and bath type ultrasonicator. Nickel Zinc Iron Oxide (NiZnFe2O4) nanoparticle is added in one of the selected emulsion which is having 10% ethanol in three different dose as additive to see the effect on the performance and emission variation of the emulsion compared with diesel fuel. The performance of the prepared sample fuels are tested on a test rig with single cylinder diesel engine. The emission is measured by using exhaust gas analyzer and smoke opacity meter. The specific fuel consumption, brake torque and brake power of E5 (95% diesel and 5% ethanol), E10 (90% diesel and 10% ethanol) and E15 (85% diesel and 15% ethanol) are evaluated and the result showed 27, 34 and 37% increment in fuel consumption; 15, 5 and 15% reduction in brake torque and the power reduction is 19, 7 and 12% respectively. E10 is selected for further test with addition of the nanoparticle with 25, 50 and 100ppm named as E103N25 (E10 with 25ppm NiZnFe2O4 nanoparticle), E103N50 (E10 with 50ppm NiZnFe2O4 nanoparticle) and E102N100 (E10 with 100 ppm NiZnFe2O4 nanoparticle). The result showed fuel consumption reduction by 16, 27 and 27% torque output increment of 1, 2 and 2% and power output increment of 5, 7 and 7% respectively compared with E10. The emission result revealed that the HC emission reduced by 50, 58 and 71% for E103N25, E103N50 and E103N100 fuel samples respectively, Carbon monoxide (CO) emission reduced by 67, 80 and 81% for E103N25, E103N50 and E103N100 fuel samples respectively. The reduction in smoke emission is reduced by 60, 69 and 61% for E103N25, E103N50 and E103N100 fuel samples respectively. Nitrogen oxide (NOX) and Carbon dioxide (CO2) emissions increased with the amount of nanoparticle added in to the fuel.

Effect of Secondary Combustion on Thrust Regulation of Gas Generator Cycle Rocket Engine

Thrust regulation is applied to maintain the performance of the liquid propellant rocket engine. The thrust level of a rocket engine can be readily controlled by adjusting the number of propellants introduced into the combustion chamber. In this study, a gas generator design is proposed in which thrust regulation is maintained by performing secondary combustion in the divergent section of the nozzle of a gas generator. Tangential and normal injection techniques have also been studied for better combustion analyses. A normal injection technique is used for the experiment and CFD results are validated with the experimental data. Chemical equilibrium analyses are also performed by minimizing Gibbs free energy with the steepest descent method augmented by the Nelder–Mead algorithm. These equilibrium calculations give the combustion species as obtained through the CFD results. Performance evaluation of the rocket engine, with and without secondary combustion in the gas generator, led to an increase of 42% thrust and 46.15% of specific impulse with secondary combustion in the gas generator.

"한국어-스페인어 기계 번역 성능 분석 연구 - 구글 번역기와 네이버 파파고를 중심으로"

This article performs performance evaluation and error analysis of the Korean-Spanish translation service engine. Unlike previous studies, the research is conducted by diversifying the types of texts to be studied and dividing them into texts with and without official translations. The translation services for study are Google Translate and Naver Papago. The translation engine performance evaluation uses BLEU score, which is one of the types of automatic evaluation, and as a result, both translation services showed relatively low evaluation scores. Also, in the case of error analysis, it is divided into four types: words, grammar, sentences, and typos. As a result of the error evaluation, word-related errors were seen the most, and the word substitution phenomenon was particularly prominent. In the case of word errors, it is characteristic that grammatical errors have a great influence on the meaning transfer of the translation, whereas there are often cases where it does not have a great influence on the meaning transfer of the translation. This study is significant in that it suggested the future direction of the development of Korean-Spanish machine translation through the evaluation of the Korean-Spanish translation service.

Performance evaluation of diesel engine using biodiesels from waste coconut, sunflower, and palm cooking oils, and their hybrids

Modern food industries are using cooking oils in the blended/hybrid form to improve fried food’s nutritional quality and taste. In the current study, biodiesels were produced from waste cooking oils of coconut, sunflower, and palm oils and their three mixtures in a 50:50 blending ratio. Fatty acid profile and properties such as density, kinematic viscosity, calorific value, cloud point, pour point, flash point, fire pint, copper strip corrosion, and carbon residue were compared for all six biodiesels. Later, the performance, combustion, and emission characteristics of a diesel engine operating with B20 blends of the six biodiesels were compared. The addition of coconut content reduced the density by 5.4 kg/m3 and 0.7 kg/m3 and kinematic viscosity by 0.837 cSt and 0.923 cSt, improved brake thermal efficiency of the engine at rated load by 0.15 % and 0.1 %, and reduced NOx emission by 25 ppm and 21 ppm, and smoke opacity by 8.5 % and 7.9 % for the sunflower and palm biodiesels, respectively. The pour point of palm-based biodiesel was reduced by 8 °C and 9 °C with the addition of coconut and sunflower oil contents. Therefore, hybridization improves the properties of the biodiesels and the performance and emission characteristics of diesel engines.

Study of pressure surge during priming phase of start transient in an initially unprimed pump-fed liquid rocket engine

In this paper, transient phenomenon during start up process of a pump fed liquid rocket engine is investigated through numerical simulation. The engine studied in this work is designed such that engine systems are not wetted with propellant until the engine is commanded to start. This is achieved by positioning the valves for propellant admission at the interface of test stand/flight stage and the engine. To evaluate engine performance during start transient for such systems, unsteady flow simulation was conducted using Method of Characteristics and equations for priming. The same has been reported in this work. The results indicated a brief period of abrupt pressure rise at pump upstream after opening of the propellant admission valves, during the process of priming of engine systems at valve downstream. The peak pressure obtained was significantly higher than the propellant tank pressure as well as the steady state pump suction pressure. The transitory pressure rise was found to occur due to flow resistance at impeller inlet caused by formation of a forced vortex for orienting the flow through impeller blades during off design transient regime. The maximum pressure at pump upstream, as computed from start transient simulation, was used as a design input for pump inlet feed lines. The engine was realized and subsequently qualified in a ground test facility. Hot test data obtained for pressure and flow rate during transient regime were found to be in good agreement with the simulation results.

Evaluation and optimization of engine performance and exhaust emissions of a diesel engine fueled with diestrol blends

AbstractBiofuel is a nontoxic and renewable fuel and could be used in diesel engines in combination with diesel to reduce emissions. The effects of various biodiesel–ethanol–diesel (BED) blends were investigated on the engine power, specific fuel consumption (SFC), engine vibration, and pollutant emissions. The engine experiments were performed using nine castor biodiesel and ethanol blends under five different engine speeds. The engine power was not influenced by different BED blends while B5E4, and B5E6 fuel blends had the highest SFC. The engine vibration slightly increased when fueled with BED blends. Hydrocarbon emission diminished by increasing biodiesel percentage in the blends, whereas it increased by substituting more ethanol in BED blends. NOx emission was increased by adding more biodiesel into BED blends, while ethanol performed vice versa. The results showed that CO emission was enhanced by increasing ethanol percentage, while it decreased with more biodiesel addition. There was not a remarkable difference in CO2 emissions between different treatments. A novel combination of an Adaptive Neuro‐Fuzzy Inference System (ANFIS) modeling and Honeybee Mating Optimization (HBMO) method was adopted to find a global optimum BED blend considering various output parameters. The selected ANFIS model satisfactorily predicted the engine efficiency and exhaust emissions with R2, mean absolute percentage error (MAPE), and root‐mean‐squared error (RMSE) of 0.99, 0.02, and 0.11, respectively. Consequently, using the HBMO algorithm, the BED blend with 15% of biodiesel, 6% of ethanol, and 79% of pure diesel was found to be the most optimal BED blend for a diesel engine at an engine speed of 950 rpm.

Performance parameters assessment of a pneumatic engine for low capacity commercial vehicles

In the present work, the performance evaluation of a low capacity pneumatic engine is shown, through modeling and simulation in order to identify the feasibility of its application in commercial vehicles for short distances. For the modeling of the pneumatic engine, a comprehensive approach has been used that includes the compressed air supply pipe, the cylinder compression - expansion chamber, and the intake and exhaust valves. The compressed air supply system is modeled using compressible fluid flow models. The fluid flow is considered adiabatic represented by the model known as Fanno flow (or non-isentropic) and it is assumed to be in a steady state. The flow in the opening and exhaust valves are evaluated as adiabatic and isentropic fluid, using a divergent - convergent compressible fluid model. The simulation results show that the feeding pressure and the pipe diameter have a great influence on the motor power. Also, the compression ratio has been found to have strong influence on the overall system efficiency. On the other hand, the simulations show that the initial pressure of the piston does not have a great influence on performance indicators, such as power or efficiency. However, from the results found in this work, it can be seen that the model and all the results obtained in this work can be used to design and generate an optimization model that describes a pneumatic engine proposed for commercial vehicles of low capacity and short distances.

Performance and emission evaluation of a marine diesel engine fueled with natural gas ignited by biodiesel-diesel blended fuel

In this paper, a marine dual fuel diesel engine fueled with the natural gas (NG: 60%, 70% and 80%) ignited by the biodiesel-diesel blended fuel (25%, 50% and 75% biodiesel by volume) was studied under different conditions. Based on the experiment, a computational fluid dynamics (CFD) model was established, and an improved chemical kinetic mechanism was developed to simulate the fuel spray process and combustion process. The ignition, combustion and emission characteristics of diesel engine fueled with different blended fuels were investigated under different load conditions. In addition, the temperature sensitivity of methane mole fraction with different NG energy fractions was analyzed at the 800 K and 1000 K. The results showed that the additions of NG and biodiesel in the blended fuel had a significant effect on the combustion and emission characteristics of the diesel engine. The starting of combustion (SOC) of the dual fuel engine lagged with the increases of NG and biodiesel content. The maximum enhancement of SOC reached 0.72°CA. The biggest influence on temperature was R122, which was the main reason for the shorter ignition delay during the combustion process. In all cases, NOx, CO and soot emissions decreased with increasing NG energy fraction. The maximum values of NOx, CO and soot emissions reached 1590 ppm, 461 ppm and 1.42 E−07 kg. Considering the combustion and emission characteristics of the engine, the best fuel blending ratio was EF80-B25.

Performance and emission evaluation of diesel engine fueled with zinc oxide-dispersed used sunflower oil methyl ester

Performance and emission evaluation of diesel engine fueled with zinc oxide-dispersed used sunflower oil methyl ester

Experimental Performance Evaluation of an Asynchronous Engine in Milking Machine

Ülkemizde ve dünyada yaygın olarak kullanılan, endüstriyel alandan evimize kadar birçok makinelerde yer alan, bakım maliyetinin az olmasıyla birlikte az arıza çıkaran asenkron motorlar süt sağma makinelerinde de kullanılmaktadır. Bu çalışmada, asenkron motorlarının dinamofren test cihazında, motor soğuk iken direnci, nominal yük altında verimliliği, motor boşta çalışırken güç ve akım değerleri, kilitli rotor testi ile motor momenti, akımı ve giriş gücü değerleri ile devrilme momenti sonuçları, aynı zamanda motor tam yük altında ve değişik gerilimlerde, sabit gerilimde değişik yüklerde akım, güç, moment ve verimlilik sonuçları incelenmiştir. Sonrasında süt sağma makinesine takılan asenkron motorun, gerilim sabit tutularak değişik vakum değerlerinde akım, güç ve devir sayılarını, vakum sabit tutularak değişik gerilim değerlerinde akım, güç ve devir sayılarının değişimleri araştırılmıştır. Bu deneysel çalışmada, Volt marka asenkron motorlardan 90-4 tipteki 0,55 kw asenkron motor, Sezer marka vakum pompası takılı olan Enka tarım süt sağma makinesinden yararlanılmıştır. Deney sonuçlarına göre asenkron motor tam yükte ve farklı gerilimler altında iken verim değeri %50,4- %68,4 arasında değişmektedir. Bu çalışmayla değişik bölgelerde kullanılan süt sağma makinelerinde bulunan asenkron motorlarının, farklı gerilim, sıcaklık şartlarında ve tam yükte çalışma durumunda, enerji tüketimi ve performansı incelenmiştir.