Performance Analysis Of Engine Research Articles

Modeling and Performance Analysis of Variable Cycle Engine with Ceramic Matrix Composite Turbine Blades

To meet the requirements of future aircraft for power systems, the turbine inlet temperatures of aero engines are gradually increasing. Ceramic matrix composite (CMC), with its higher thermal limit, has become the preferred material for the turbine blades of variable cycle engines (VCEs). However, the impact of CMC turbine blades on the performance of a VCE is still unknown. In this research project, the comprehensive cooling-efficiency characteristics of CMC are determined through a fluid–solid coupling calculation; a cooling calculation model for turbine blades is established, and cooling airflow solution and control technology (CSCT) for an air system is developed. Additionally, a VCE simulation model is established to analyze the influence of CMC turbine blades on the cooling airflow of the air system and the overall performance of the engine. The results show that, for the design condition, the CMC turbine blade can reduce the cooling airflow of the air system by approximately 10%, and the net thrust is increased by 6.07–7.98%. For the off-design conditions, with the CSCT, the specific fuel consumption can be reduced by 3.06–5.73% while ensuring that the engine net thrust remains unchanged. A comprehensive analysis of the performance for both the design point and off-design points indicates that the use of CMC for high-pressure turbine (HPT) guide vanes and rotor blades yields significant performance benefits, while the performance improvement from the use of CMC for low-pressure turbine (LPT) rotor blades is minimal.

0D-1D coupled method for performance design and analysis of adaptive cycle engine - Modeling, simulation and validation

0D-1D coupled method for performance design and analysis of adaptive cycle engine - Modeling, simulation and validation

Performance analysis of dual-fuel engines using acetylene and microalgae biodiesel: The role of fuel injection timing

This study evaluates the impact of varying fuel injection timing (FIT) and dual-fuel modes on the performance and emissions of a compression ignition (CI) engine under different load conditions. The biodiesel used was derived from Chlorella protothecoides microalgae through a two-step transesterification process, and its elemental composition was characterized using gas chromatography-mass spectrometry (GC-MS). Acetylene gas was introduced into the engine intake manifold at a rate of 3 L per minute (LPM), while a blend of 20 % methyl ester from Chlorella protothecoides (B20 MEOA) served as the primary injected fuel. To predict engine performance and emission characteristics, advanced machine learning models were employed and evaluated using four statistical criteria, including R-squared, mean absolute error (MAE), and mean squared error (MSE). Experimental results indicated that the optimal configuration involved a dual-fuel mode combining B20 MEOA with acetylene gas and an advanced FIT of 25° before top dead center (bTDC). Performance analysis revealed that under all load conditions, the specific fuel consumption (SFC) decreased by 7.3 %, while brake thermal efficiency (BTE) increased by 1.6 % compared to conventional diesel. Emission testing showed a 7.6 % rise in nitrogen oxide emissions, alongside significant reductions in unburned hydrocarbons (12.5 %), carbon monoxide (25.6 %), and smoke intensity (7.5 %) relative to standard diesel operation. Optimization of the engine parameters ensured that key metrics, such as brake power (BP) and brake-specific fuel consumption (BSFC), remained within acceptable limits. The random forest model outperformed other machine learning models, demonstrating superior accuracy in predicting performance and emissions across all statistical measures. This study underscores the potential of combining advanced biodiesel blends with optimized FIT strategies to improve engine efficiency and emissions control, offering a promising approach for sustainable dual-fuel engine operations.

Comparative analysis of spark ignition engine performance using RON 95 and RON 100 gasoline fuels

Most of the vehicles used by Malaysians have engines that only require petrol RON 95 to power the engine. However, many people claimed that utilising RON 100 instead of RON 95 for their vehicles will improve engine performance. Furthermore, many people speculate that using oil with a low octane level in an engine with low performance will affect the engine's performance. The goal of this research is to analyse and compare the engine performance and emissions on a spark ignition engine using gasoline RON 95 and RON 100. In this study, a single-cylinder four-stroke engine running with RON 95 and RON 100 has been tested on an engine dynamometer to evaluate the brake power, torque, specific fuel consumption, and exhaust emissions. The emissions from the engines have been determined using a gas emissions analyser. The outcomes of the experiment have been analysed based on engine torque, braking power, and exhaust emissions. Based on the analysis, torque, brake power, and emissions data obtained from the dynamometer engine, RON 100 has a higher and smoother performance than RON 95.

Natural gas-fueled HCCI engine performance and emission analysis and comparison with SI and spark-assisted operations

ABSTRACT The homogeneous charge compression ignition (HCCI) engine is a promising technology in terms of both soot and NOx emission. Natural gas (NG) is advantageous especially for HCCI engines with its single stage combustion, low C/H ratio, and high octane number. Since the main challenge of HCCI technology is stability and transient operations, using HCCI for constant speed operations may be advantageous. In this study, a CI diesel engine, which is used as a generator at constant speed, was modified and converted into an NG-fuelled, SI engine. Then, the engine was supplied with NG for SI, HCCI, and spark-assisted HCCI experiments. Spark-assisted operations were executed by using 3, 5, and 7 degree ignition advance values to assist HCCI combustion. In-cylinder pressure variations, exhaust temperature, specific fuel consumption, and emission values were investigated for comparison of different strategies. Experimental results showed that using the HCCI strategy and retardation of ignition advance of spark-assisted HCCI operations reduced maximum pressure. Therefore, these strategies improved NOx emissions, while HC emissions were slightly increased. The spark-assisted HCCI strategy improves the stability of operation while increasing CO emission. The specific fuel consumption value of HCCI was slightly higher than that of SI operation, while it was lower than spark-assisted strategies.

Performance analysis of the adaptive cycle engine with cooling air: From propulsion performance, thermodynamic efficiency, exergy and infrared characteristics

The adaptive cycle engine gains significant attention due to its variable thermodynamic cycles and multi-duct characteristics, which are utilized for thermal management to enhance engine performance. This paper explores the features of multi-duct technology in adaptive cycle engines and aims to improve engine flight performance. An analysis is conducted on the impact of duct air bleed on engine propulsion characteristics, thermodynamic cycle properties, and exhaust system infrared radiation characteristics. Initially, a component-level model of the adaptive cycle engine was established, considering CDFS duct, bypass duct, and third duct air cooling devices. This model uses the ducted cold air to cool the temperature of low-pressure turbine exit, center cone wall, and main nozzle expansion section wall. Subsequently, a method for analyzing the infrared radiation of the engine exhaust system was proposed based on the above model, and the performance of engine components and the overall engine was analyzed in terms of energy, exergy, mechanical efficiency, and thermal efficiency. Finally, the numerical simulations of the propulsion performance, thermodynamic efficiency and infrared characteristics of the adaptive cycle engine with cooling air were carried out under conditions of ground takeoff, subsonic cruise, and supersonic cruise. The simulation results show that the cooling air can effectively enhance engine performance and infrared stealth capabilities under various flight conditions. The ducted air extraction measures proposed in the paper could effectively improve the propulsion efficiency and stealth characteristics of the engine, providing important references for the development of more efficient aeroengine.

Performance analysis of quantum harmonic Otto engine and refrigerator under a trade-off figure of merit

Abstract We investigate the optimal performance of the quantum Otto engine and refrigeration cycles of a time-dependent harmonic oscillator under a trade-off figure of merit for both adiabatic and nonadiabatic (sudden-switch) frequency modulations. For heat engines (refrigerators), the chosen trade-off figure of merit is an objective function defined by the product of efficiency (coefficient of performance) and work output (cooling load), thus representing a compromise between them. We obtain analytical expressions for the efficiency and coefficient of performance of the harmonic Otto cycle for the optimal performance of the thermal machine in various operational regimes. Particularly, in the sudden-switch regime, we discuss the implications of the nonadiabatic driving on the performance of the thermal machine under consideration and obtain analytic expressions for the maximum achievable efficiency and coefficient of performance of the harmonic Otto thermal machine. Particularly, we show that the quantum harmonic Otto cycle driven by sudden-switch protocol cannot work as a heat engine or refrigerator in the low-temperature limit. Finally, we show that in the high-temperature limit, the frictional effects give rise to a richer structure of the phase diagram of the harmonic Otto cycle. We identify the parametric regime for the operation of the Otto cycle as a heat engine, refrigerator, accelerator, and heater.

Educating Engineers on the Use of Renewable Ethanol Fuel as a Drop-in Replacement for Gasoline in Small Engines

The use of high-blend ethanol fuels to reduce emissions produced by on-road vehicles has been extensively studied. However, much less research has been done to study the effect of operating small off-road engines on high-blend ethanol fuel as a drop-in replacement for gasoline. Most small engine manufacturers only certify proper operation on low ethanol blends such as E10 (10% ethanol, 90% gasoline by volume). Most engineering students are unaware of the benefits that can be achieved when using high-blend ethanol fuel in small engines without substantial modifications. In this study, students conducted performance testing and analysis of a small engine using a dynamometer and a raw exhaust emissions analyser. The exhaust emissions and performance of the engine were evaluated using the U. S. Environmental Protection Agency (EPA) 6-mode duty cycle for small recreational engines (under 19 kW). Testing and analysis followed the recommendations of the SAE J1088 recommended practice. Students were motivated by the contemporary nature of the project and the use of commercially available equipment for testing. Further, students learned about the use of standardized testing to demonstrate the performance and emissions results.

Analysis of Engine performance and Emission of HPLPM Exhaust with Catalytic Converter Distance Variation

Analysis of Engine performance and Emission of HPLPM Exhaust with Catalytic Converter Distance Variation

Comparative performance and emission analysis of internal combustion engine and battery electric vehicle under modified Indian drive cycle

This study deals with an analysis of the performance and emissions characteristics of an automotive Compression Ignition Engine Vehicle (CIEV) with 86 kW rated power output fueled with diesel in comparison to a grid based Battery Electric Vehicle (BEV) with 86 kW Electric Motor under the Modified Indian Drive Cycle (MIDC) using the simulation. A novel methodology for undertaking the comparative analysis is developed to assess the CIEV and BEV performance for different scenarios under wide operating conditions. The results indicate that energy consumptions for CIEV and BEV under the MIDC cycle are 2653.1 kJ/km and 416.72 kJ/km. The net effective carbon price during fuel production and vehicle operation is Rs 0.20 per km for CIEV which is 80 % more than Rs 0.11 per km for BEV. A BEV also has an initial carbon debt due to battery production which is 27 times that of CIEV, however, this penalty is easily recovered within a short period against the lower running costs of BEV. The range of the ICE power source is estimated to be 5.85 times that of the EV for MIDC. By increasing the battery capacity five fold, the range of EV can be enhanced, however considerable weight penalty is levied. The levelised cost of transportation for one lakh kilometers was assessed wherein it was found that ICE vehicle expenditure is approximately Rs 25.59 per km against Rs 23.31 per km of BEV.

Experimental analysis and modeling of gas turbine engine performance: Design point and off-design insights through system of equations solutions

In this article, a systematic approach is presented for simulating turbojet engine performance at both design and off-design points. The construction of gas turbine engines involves a core, with additional components added based on the proposed methodology. Accurate formulation of component characteristics and their matching forms the basis for the system of equations needed for solving off-design engine performance. The developed algorithm's initial step involves comparing results with experimental data obtained from 230 N engines. Experimental testing utilizes a 780 N engine under diverse operating conditions, allowing determination of thrust values, fuel consumption, and outlet gas temperatures. An engine characteristic curve is derived under static conditions at ground level and validated against ground test results in Tehran. Unknown parameters are calibrated using a dedicated model, enabling the extraction of engine performance parameters across different corrected speeds. These results are then compared with GasTurb outputs. Comparative analysis between the proposed model's simulation and experimental data demonstrates high accuracy, affirming the reliability of the presented model.

Experimental Investigation of Energy Analysis of Methanol-Gasoline Mixtures at Different Torque Values

Despite the increasing use of petroleum-based fuel as a result of ever-increasing energy demands, the search for alternative fuels remains important. In this study, in a Lombardini LGW 523 brand 2-cylinder 4-stroke water-cooled engine, different volumetric ratios of methanol and gasoline fuel mixtures (M10, M20, M30, M40) were used at 4 different torque values (5, 10, 15, 20 Nm) at a constant 3000 engine speed. It is discussed. As a result of the study, engine performance, emission and energy analysis examination was carried out experimentally. Keywords: Energy, exergy, internal combustion engine, methanol fuel

Performance, emissions and combustion analysis of hydrogen-enriched compressed natural gas spark ignition engine by optimized Gaussian process regression and neural network at low speed on different loads

The transportation industry is increasingly focused on hydrogen based fuel as a promising alternative due to its potential for reduced emissions and enhanced performance. The purpose of this study is to improve efficiency and reduce emissions on low speed on different loads for heavy duty vehicles. This study can be impactful to train the electronic control unit (ECU) for heavy duty vehicles working on aforementioned conditions. This study investigates the effect of hydrogen ratios (0%–40 %) in HCNG, (0%–15 %) exhaust gas recirculation (EGR) ratios, and spark timing (8°-34o CA bTDC) at low and high loads (15 % & 75 %) under stoichiometric conditions at low speed (700 rpm). Performance, emissions and combustion parameters were thoroughly analysed across these conditions. Brake thermal efficiency increases by 20.7 % & 19.4 % by the addition of (0 %–40 %) hydrogen at low and high load at 14o CA bTDC running on 5 % and 0 % EGR respectively. NOx emissions reduces by 11.9 % & 17.9 % by the addition of (0 %–15 %) EGR and increases by 46.1 % & 46.4 % by increasing the amount of hydrogen in HCNG at low and high load at 14o CA bTDC at 0 % EGR respectively. Coefficient of variation reduces 13.8 % by (0 %–40 %) hydrogen addition at 11 % EGR at 16o CA bTDC. Optimized Gaussian process regression (GPR) and neural network (NN) machine learning techniques were applied to the dataset, and found GPR matern 5/2 is best one. The findings can be utilized in the development of HCNG engine.

Decarbonization strategies in the maritime industry: An analysis of dual-fuel engine performance and the carbon intensity indicator

This study is based on detailed data from 11 sea voyages over three years to determine the impact of liquefied natural gas (LNG) use on the decarbonization pathway in maritime transportation. The research detailed the vessel's daily fuel consumption, CO2 emission inventories, and Carbon Intensity Indicator (CII). The decision tree method used to evaluate this complex dataset highlights the possible contributions of LNG to maritime energy efficiency and sustainability. While the findings show that LNG reduces CO2 emissions by around 30 %, it is insufficient to meet the International Maritime Organization's (IMO) 2050 targets. The study concludes that LNG should be an important transition fuel until the mid-2030s. However, the maritime sector needs multi-pronged strategies such as technological innovations, stringent regulations and sectoral collaborations to achieve a decarbonized future. This research provides a comprehensive analysis assessing the potential of LNG to achieve the IMO 2050 targets in the context of maritime decarbonization strategies.

High-Fidelity Simulation and Performance Analysis of Twin-Spool Turbofan Engine Based on Multi-dynamics Approach

High-Fidelity Simulation and Performance Analysis of Twin-Spool Turbofan Engine Based on Multi-dynamics Approach

Performance analysis of a gas turbine engine with intercooling and regeneration process - Part 1

Abstract Auxiliary systems, such as regeneration and intercooling, have been integrated with the primary gas generator to improve power production and fuel economy in modern gas turbine power plants. Implementing these techniques in turbine engines is challenging due to size, weight, and complex flow patterns. A solution is to use a turboprop engine with a smaller mass flow rate and simpler gas paths. The current study involves the numerical analysis of performance parameters namely, specific power (SP), thermal efficiency (η), and enthalpy based specific fuel consumption (EBSFC) of a turboprop engine using thermodynamic parameters namely, pressure ratio (PR), nozzle pressure ratio (NPR), turbine inlet temperature (TIT), regeneration efficiency (R), and intercooling efficiency (E). The results prove that the introduction of regeneration and intercooling showed significant improvement in the power developed, and reduced fuel consumption.

Performance analysis of a constant-speed LPG engine

Performance analysis of a constant-speed LPG engine

EXHAUST GAS ANALYSIS OF DIESEL - CADOBA FARINOSA FORSKK BIO-ETHANOL BLENDED FUEL SAMPLES RUNNING ON COMPRESSION IGNITION ENGINE

The world is facing declining liquid fuel reserves at a time when energy demand is exploding. As the supply decreases and costs rise, everyone will be forced to adopt the alternative energy resources. In order to achieve a secure and stable energy supply that does not cause environmental damage, renewable energy sources must be explored and promising technologies should be developed. This study investigates the effects of exhaust gases of diesel-Cadoba farinosa forskk bio-ethanol blended fuel samples run on a compression ignition engine. The test fuels were prepared; BDE2 (97% Diesel and 2% bio-ethanol volumetric proportion), BDE4, BDE6, BDE8 and BDE10 with 1% biodiesel (palm oil methyl esters) was maintained throughout to prevent phase separation of the ethanol and diesel respectively. The engine performance and exhaust gas analysis were also conducted to investigate the effect of bio-ethanol as diesel fuel extender, with a TD110-115 single-cylinder, four-stroke and air-cooled, compression ignition engine test rig, under different loading conditions, and incorporated with an SV-5Q automobile exhaust gas analyzer was used to monitor and measure the concentration of gaseous emissions, such as; exhaust gas temperature (EGT), carbon dioxide (CO 2), carbon monoxide (CO), and unburned hydrocarbon (HC) from the engine tail pipe. Results of the test revealed an appreciable increase in exhaust gas temperature of 16.66% due to the rise in cylinder pressure and temperature respectively. An appreciable decrease in HC, CO and CO 2 15.7%, 37.5% and 15% respectively emissions was recorded for all blended fuel samples with the exception of diesel. While, the least CO and CO 2 emission levels were observed for BDE10 fuel samples. On the account of its satisfactory engine performance behavior, fuel conservation advantages, and inherent greenhouse gas mitigation potentials, the candidacy of Cadoba Farinosa Forskk bio-ethanol and diesel blends, offers the promise of a prospective fuel for compression ignition engines.

Green Energy from Palm Kernel Shell Gasification – dual fuel engine performance analysis

<span lang="EN-US">Electricity generation in Indonesia is mainly generated from non-renewable fuels. Based on these problems, this research utilizes palm kernel shells to be converted into producer gas as secondary fuel for a 5 kW diesel engine. Through a gasification process equipped with a cooling and gas cleaning system, low tar gas is fed to the diesel engine with variations of gas flow rate ratio to combustion air. A dummy load is installed to investigate the effect of load on diesel consumption. The diesel engine vibration increases due to using two fuel types was measured by installing a vibration meter. The research results show that the higher the load and the greater the ratio of producer gas injected, the less diesel consumption. At a gas ratio of 4:1 and an increase of load from 1 to 5 kW, the diesel fuel flow rate reduces by 25 - 31%. The most significant reduction in diesel consumption occurred at a load of 5 kW, valued at 38.49%. On the other hand, increasing the gas ratio causes an increase in diesel engine vibration. The research results showed an increase in engine vibration of 5.84% - 10.25%. The largest vibration was recorded at a load of 5 kW with a value of 92.4 m/s<sup>2 </sup> </span>

Performance analysis of a gas turbine engine via intercooling and regeneration- Part 2

Abstract The current study aims to amplify the predictive ability of the numerical model developed for a gas turbine engine-based power plants by process of regeneration and intercooling. Artificial neural networks (ANN) and adaptive neuro-fuzzy interface systems (ANFIS) are the two techniques mainly concentrated in this study which were not properly implemented previously. The performance parameters namely, specific power (SP), thermal efficiency (η), and enthalpy based specific fuel consumption (EBSFC) of a Turboprop engine were predicted using thermodynamic parameters namely, pressure ratio (PR), nozzle pressure ratio (NPR), turbine inlet temperature (TIT), for constant regeneration (R), and intercooling (E) efficiencies. The results showed that a high regression result R 2 of 0.9831 and 0.9899 was found for the ANFIS model for η for training and testing, respectively. Also, the ANFIS model resulted in best performance of the performance characteristics when compared to ANN.