Combustion Chamber Components Research Articles

Experimental investigation of ternary blends on performance, and emission behaviors of a modified low-heat rejection CI engine

This study investigated the performance, combustion, and emissions of a modified low heat rejection (LHR) diesel engine fueled with a blend of 90 % coconut waste cooking oil (CWCO) biodiesel and 10 % diethyl ether (DEE). The engine combustion chamber components were coated with 300 μm lanthanum-doped partially stabilized zirconia for thermal insulation. Engine testing was performed at varied loads from 0 to 100 % using an eddy current dynamometer. Exhaust emissions, including hydrocarbons (HC), carbon monoxide (CO), nitrogen oxides (NOx), and smoke were measured. Compared to conventional diesel, the CWCO-DEE blend showed a 3 % higher brake thermal efficiency of 33.4 % and 2.42 % lower brake-specific fuel consumption at full load. HC, CO, and smoke emissions decreased by 18 % (39 ppm), 11 %, and 19 % at higher loads with the blend. However, NOx emissions increased slightly by 21.2 %. The DEE compensated for CWCO's lower cetane number and viscosity, while the LHR coating enhanced combustion by providing thermal insulation, raising exhaust gas temperatures by 13 %. The improved efficiency and reduced emissions demonstrate the potential of optimized biodiesel-additive blends in conjunction with LHR engine modifications to sustainably utilize inexpensive waste cooking oil feedstocks as renewable diesel replacements. However, further optimization of blend compositions, additives, and coatings is needed to balance performance benefits against possible NOx increases. This study highlights a promising combined approach leveraging engine design and fuel advancements.

Theoretical and numerical investigation of introduced errors in surface temperature measurements of pistons applied in internal combustion engine

DMP (Differences in Material Properties) often exists between temperature sensors and combustion chamber components of ICE (Internal Combustion Engine), resulting in IEs (Introduced Errors) in the temperature measuring process. In this paper, we present a comprehensive theoretical analysis of the correlation between introduced errors on chamber components and the DMP. The analysis process considers the characteristics of the chamber's heat transfer BC (Boundary Condition). Then, simulations are used to investigate the introduced error of hardness plug and thermocouple sensors on the top surface of an ICE aluminum alloy piston. The theoretical analysis results indicate that heat transfer BC can be segmented into the time-averaged and fluctuation parts, and IEs are linearly superimposed under these two parts of BCs. The heat conductivity impacts the time-averaged error and the product of heat conductivity, density, and heat capacity impacts the fluctuation error. The experimental and simulation results indicate that the max time-average error of the hardness plug on piston is 2.4 °C, with a fluctuation introduced error of 3.6 °C and a total introduced error of 6 °C; and the time-average introduced error of thermocouple sensor is 9.4 °C, with a fluctuation error of 5.8 °C and a total introduced error of 15.2 °C. Finally, a fluctuation error correction method is proposed to reduce error. After correction, the error is reduced by 71 % and 66 % for hardness plug and thermocouple, respectively.

An Innovative Retrofit Design for Energy Efficiency and Emission Reduction: MAN B&W Marine Engine Slide Fuel Injector

Background:: The fuel injector is one of the most essential parts in marine diesel engines. For MAN B&W two-stroke engines, the conventional fuel injector, due to the existence of sac volume, can result in problems such as increased emission and fuel consumption and shortened service life of combustion chamber components. Objective:: The MAN B&W marine engine slide-type fuel injector is a structural retrofit of conventional injectors, improving diesel engine combustion conditions, fuel efficiency, and emission reduction in hydrocarbon, NOx, smoke, and particulate matter by eliminating sac volume with patented technology. Methods:: This study employed a comparative analysis approach to evaluate the performance of conventional fuel injectors versus slide-type fuel injectors in MAN B&W two-stroke engines. Data collection involved practical experiences, onboard operations, and analysis of fuel efficiency, emission reduction, and combustion improvement. The structural differences and operational advantages of both injector types were examined to assess the environmental benefits and economic implications of adopting slide fuel injectors. Recommendations for the gradual replacement of conventional injectors with slide-type injectors were based on empirical data and industry best practices. Results:: Slide fuel injectors obtain a reduction of about 75% of the HC emissions at all loads. The slide fuel injector significantly decreases the smoke emission level at low engine load, at 25% load. A reduction in PM of up to 50% has been confirmed, and slide fuel injectors can reduce NOx emission by approximately 15% on average. result: The smoke emission level at low engine load, at 25% load in particular, is greatly decreased by slide fuel injector. Conclusion:: Slide fuel injectors, with a granted patent, are commonly used in marine low-speed engines due to their advantages.

Analysis of the effect of the number of injector nozzles on the pressure and heat transfer coefficient in a hydrogen-diesel mixture diesel engine

In reciprocating internal combustion engines, the calculation of the heat transfer coefficient (HTC) is essential to estimate the heat transfer during combustion in the combustion chamber. The HTC calculation takes into account fluid flow and combustion processes and varies as a function of crank angle and location within the chamber. The mean HTC value is commonly used to calculate the thermo-mechanical analysis of various combustion chamber components. In this study, dynamic grids for the intake port, exhaust port and chamber are created in the chamber modelling section of the AVL-Fire software. The intake and combustion processes are then simulated and the calculated pressure data are compared with experimental data at 2800 rpm with 1, 3 and 6 hole injectors. Finally, the distribution of HTC over the chamber walls was evaluated using a time step method. The research also included verification of the HTC results with theoretical data obtained by Woschni and Hohenberg. In addition, with the decreasing availability of fossil fuels and the need for lower exhaust emissions from diesel engines, the use of blends of diesel and hydrogen fuel has become widespread. In this engine, a mixture of 10 % hydrogen and 90 % diesel fuel is used. The final results show that the heat transfer coefficient increases by approximately 1.72 % when hydrogen is added to diesel fuel due to the number of collisions between hydrogen and other fuel components.

Динамічні процеси у твердопаливних ракетних двигунах та їх взаємодія з вібраціями конструкції ракети: стан питання та актуальні проблеми

The most critical operating conditions of solid rocket motors (SRMs) are often due to the development of dynamic processes characterized by excess values of operating parameters. Pressure surges and a sharp increase in the combustion product temperature may impair the strength of the combustion chamber structure, cause its failure, and lead to critical conditions of the motor operation, up to extinguishing the propellant combustion in the motor. It is shown that both in steady and in unsteady operating conditions of an SRM, dynamic processes in its combustion chamber feature a complex interrelation of a large number of processes in the gas-dynamic space of the combustion chamber: physical, chemical, and thermodynamic (heat and mass exchange) processes. It is found that current studies of SRM operation instability are aimed at identifying mechanisms of combustion chamber pressure oscillations, which are usually due to combustion product vortex formation in the chamber space and acoustic feedback resulting from collisions of vortices with the SRM’s combustion chamber components or nozzle. Other lines of investigation are the analysis of SRM resonant damping and the establishment of a relationship between aluminum droplet combustion and SRM internal instability. It is noted that accelerations and vibrations of mixed-propellant combustion surfaces may greatly affect the combustion rate and the agglomeration, on-surface confinement, and burn-up of metal additives, which, in its turn, governs the combustion chamber acoustics. It is pointed out that the interaction of SRM combustion chamber pressure oscillations and the response of the SRM structure observed in flight tests of some rockets should be taken into account in predicting the stability of SRM dynamic processes. This interaction may call into question the sufficiency of SRM static tests and subsequent conclusions on the magnitude of its dynamic effect on the rocket structure.

Effects of critical plasma spraying parameters on microstructure and mechanical properties of LaPO4-8YSZ thick composite coatings

LaPO4-8YSZ composite coatings with a thickness of ∼1 mm have been developed for increasing thermal protection of combustion chamber components in gas turbines and diesel engines. A serious problem concerning the thick coatings is the high residual stress, which results in poor adhesion and low thermal shock resistance. In this study, thick LaPO4-8YSZ composite coatings in different compositions were produced by atmospheric plasma spraying at four different critical plasma spraying parameters (CPSP; 0.83, 0.94, 1.06 and 1.17 kW/Lpm). The effects of CPSP on microstructure, residual stress and mechanical properties of LaPO4-8YSZ thick composite coatings were investigated. The results shows that the porosity of the coatings is decreased with the increase of CPSP from 0.83 to 1.17. The decreasing porosity leads to the increase of Young’s modulus and microhardness of the coatings, while the fracture toughness of the coatings shows a decreasing tendency. The residual stress in the composite coatings increases with increasing CPSP. Correspondingly, the thermal shock resistance of the coatings decreases with the increase of CPSP. The 5 wt% LaPO4-8YSZ composite coating has the lowest residual stress at CPSP 0.83 and it exhibits the longest thermal cycle life at 1000 °C (1355 ± 134 cycles).

Effective Utilization of Waste Cooking Oil Methyl Ester-Diesel blends in a Semi-Adiabatic CI Engine – An Experimental Approach

The utilization of energy produced in an internal combustion (IC) engine plays a key role in improving engine performance. Thermal Barrier Coating (TBC) is one of the effective engine modification methods to utilize the energy effectively in an IC engine. The alternative fuels with very poor fuel properties can be fuelled successfully in a TBC mode. In this study, an investigation was carried out in a TBC, single-cylinder, diesel engine fuelled with waste cooking oil-diesel blend. In the first phase, the waste cooking oil methyl ester (WCOME) is fuelled in the standard engine for the performance, combustion and emission characteristics. In the second phase, the WCOME blend with diesel to an appropriate percentage of 20% by volume (WCOMEB20) and tested in the standard engine for the characteristics. In the third phase, the standard engine is converted to TBC mode. The engine combustion chamber components such as piston crown, cylinder head, inlet and exhaust valve were coated with bond coat nickel, chromium, aluminium alloy (NiCrAl) thickness 100 microns and ceramic coat of 8% yttria stabilized zirconia (8%YSZ) with a thickness of 200 microns. In the fourth phase, the WCOMEB20 was fuelled in the TBC mode for the characteristics and finally, the results were compared. From the experimental result, it was come known that WCOMEB20 showed betterment in the fuel properties such as viscosity, density, and cetane index compare with the neat WCOME. The substantial improvement in the performance and exhaust emissions such as carbon monoxide (CO), unburnt hydrocarbon (UHC), and smoke opacity with WCOMEB20 compared with neat WCOME. Furthermore, the TBC mode fuelled with WCOMEB20 experienced a supreme enhancement in the performance, combustion and emission except nitric oxide (NO). This improvement was due to the betterment in the fuel properties with WCOMEB20 and high in-cylinder temperature with TBC which enhanced the combustion and reduce the unburnt charges present inside the combustion chamber. From the above finding, it was concluded that WCOMEB20 fuelled with TBC mode was an effective fuel and engine modification technique to improve the performance, combustion and emission characteristics of a diesel engine.

Experimental analysis of the combined effect of thermal barrier coating material and the nanoparticle augmented fuel usage on CI engine characteristics

The scope of this work involves the utilization of optimal insulating material and nanoparticles in addition to diesel for enhancing the CI engine performance reduce harmful environmental emissions. The first phase of the research work focused on coating the combustion chamber components, including cylinder-liner as well as a piston with 150 and 100 μm thickness, correspondingly, with equivalent quantities of Yttria Stabilized Zirconia (YSZ) and Alumina (Al2O3) powder using the plasma spraying method. The second phase of experimental work oversees the augmentation of diesel fuel with 30 ppm and 60 ppm of Cerium Oxide (CeO2) nanoparticles independently. Initially, the effectiveness, as well as emissions criteria, were investigated using a thermal barrier coated (TBC) engine & neat diesel. The implications of CeO2 nanoparticles were then compared with the reference engine. Usage of the thermal barrier coated chamber reduced the specific fuel consumption (SFC) by 7.71 % and increased the brake thermal efficiency (BTE) by 1.75 %. Additionally, the SFC was reduced by 8.25 % and 13.19 %, and the BTE was enhanced by 2.43 % and 3.54 % in the TBC engine, which used 30 ppm and 60 ppm CeO2 mixed diesel fuel, respectively, when correlated with the reference engine. Besides, harmful pollutant gases of carbon monoxide (0.0707 % vol), hydrocarbon (37 ppm), and smoke (8.08 %) were minimized extensively by TBC coating material usage and the inclusion of nanoparticles in the fuel.

Use of La2O3 with 8YSZ as thermal barrier coating and its effect on thermal cycle behavior, microstructure, mechanical properties and performance of diesel engine operated by hydrogen-algae biodiesel blend

In this present work, the effect of lanthanum oxides (La2O3) on the thermal cycle behavior of TBC coatings and mechanical properties such as adhesion strength and microhardness of 8% Yttria Stabilized Zirconia (8YSZ) TBCs were investigated. CoNiCrAlY and aluminium alloy (Al–13%Si) were used as bond coat and substrate materials. 8YSZ and different wt % of La2O3 (10, 20, and 30%) top coatings were applied using the atmospheric plasma spray (APS) method. The thermal cycling test for TBC coated samples were conducted at 800 °C in the electric furnace. The XRD pattern shows that the La2O3 doped 8YSZ material transformed to cubic pyrochloric structured La2Zr2O7 during thermal cycling. Further, the Taguchi-based grey relation analysis (GRA) method was applied to optimize the TBC coating parameters to achieve better mechanical properties such as adhesion strength and microhardness. And the optimized La2O3/8YSZ TBC coating was coated on CRDI engine combustion chamber components. The engine was tested with microalgae biodiesel and hydrogen, and the results were promising for the TBC-coated engine. The engine performance increased while using La2O3/8YSZ coated components, and the emissions from engine exhaust gas such as CO, HC, and smoke reduced considerably. It was found that there was no separation crack and spallation of the coating layer in the microstructure. Ultimately, the microstructural analysis of the optimized TBC coated piston sample after 50 h of running in the diesel engine confirmed that the developed coating had a superior thermal insulation effect and longer life.

Study of In-Cylinder Heat Transfer Boundary Conditions for Diesel Engines Under Variable Altitudes Based on the CHT Model

The reliability of combustion chamber components is mainly determined by the thermal load of diesel engines. Under the plateau operation condition, diesel engine performance degradation and ablation area appear. Therefore, it is crucial to study the engine heat transfer phenomenon at different altitudes, of which the Woschni formula cannot meet the accuracy requirement. With the motive of modifying and calibrating the Woschni formula at different altitudes, a modified conjugate heat transfer (CHT) model of the combustion chamber and the cooling medium was proposed to analyze the temperature distribution of the cylinder head. The results indicated that relative errors were controlled within 5% under variant altitudes, comparing the temperature field of the numerical simulation with the single-cylinder engine experiment test data. Therefore, the modified in-cylinder conjugate heat transfer model can be used to predict the thermal load of diesel engine combustion chamber components under different altitude operating conditions.

Torsional Overload Fracture of Twist-off Bolts During Assembly

Abstract Supposedly simple cases of failure are most often best suited to communicate the principles of component failure analysis in the field of materials engineering to a wide readership, especially to those peers in the specialist community who are just beginning to familiarize themselves with the subject. The present case of failure relates to components that failed as early as during the assembly, and more specifically, during the final assembly stage of combustion chamber components for heavy-duty gas turbine engines. Hence, they lost their functionality (in fact, the common definition of component failure). At tightening torques of the nuts opposite of the tapered heads as low as below 25 Nm, so-called twistoff bolts which, when welded into combustion chamber sheets, take on the function of stud bolts, sheared off. By way of exception, a materialographic failure analysis could show that the primary cause of the failure was not the component’s design, but the disregard of the drawing specifications during final assembly. However, on a secondary level, design deficiencies had to be mentioned, as untempered welded joints in martensitic chromium steels invariably act as metallurgical notches. If the respective part is subjected to dynamic loads, as is the case in virtually all turbo machinery, they are thus to be avoided.

Thermal fatigue analysis of different nano coating thickness by air plasma spraying in diesel engine thermal barrier coating

Abstract The use of Atmospheric Plasma Spraying (APS) and yttria stabilized zirconia (YSZ) nanostructured coatings has been applied to the bond layer of NiCrAlY coated engine cylinder heads, pistons, and valve substrates. Thermal barrier coatings (TBCs) have been utilized to increase the engine performance in the design of combustion chamber components for internal combustion engines. ASTM-C-633-01 standard has been employed to conduct the bonding strength testing. It was also considered and directed to estimate the coating’s thermal performance by evaluating its insulation value and conducting a thermal insulation durability assessment. Field emission scanning electron microscope (FESEM) and X-ray diffraction (XRD) were used to look at the nano powders and coatings’ microstructures and phase compositions. In YSZ, it was discovered that the topcoat of samples had a tri-modal pattern of nano sized particles engaged by the powder, micro-columnar grains generated from the re-solidification of the molten part of the powder, and almost equiaxed grains, which were a unique construction feature. The results demonstrated the creation of nano zones in one of three nanostructured coating zones and improved the top coating properties, including bonding strength and thermal insulation capacity. The high temperature of the diesel engine caused fatigue failure in the intake and exhaust valves.

Investigation of the co-firing of natural gas and RDF in a model combustion chamber**

The production and utilization of fuel derived from municipal solid waste (RDF/SFR) is an effective method for saving organic fuel and decreasing emissions of harmful substances and greenhouse gases at landfill and refuse dumps. Ukraine has a potential for the production of 1.5–2 million tons of RDF/SFR with a calorific value of 10–25 MJ/kg annually. In the case of involving these fuels to power sector, about 2500 GW-h of electricity and 4500 GW-h of heat can be produced annually. One of the promising variants to involve RDF/SFR to power sector is their combustion, including co-firing with natural gas, aimed at the production of heat and electricity, in particular, using the existing boilers of small and middle steam capacity in compliance with stringent ecological requirements (Directive 2010/75/EU etc.).
 For performing this investigation, we chose a GMP-16 gas-and-oil-fired burner, mounted into a cylindrical combustion chamber. The gas-and-oil-fired hot-water boilers of KVGM grade, designed for heating and hot water supply, are equipped with burners of this type. In computer modeling, we determined the influence of RDF additions on the co-firing with natural gas for a given geometry of the combustion chamber components (with a burner of 18.6 MW heat output). We obtained calculated dependences of temperatures, velocities, distributions of gas component concentrations, carbon remained in the solid phase, as well as the concentrations of nitrogen oxides and carbon monoxide over the combustion chamber. According to preliminary assessments, we established that additions of up to 20% RDF/SFR (by heat at input) in their co-firing with natural gas will not change substantially the technical and ecological parameters in operation of the combustion chamber.

Результаты испытаний модельной кислородно-метановой камеры сгорания жидкостного ракетного двигателя, созданной с использованием методов аддитивного производства

The paper focuses on an experimental unit developed for modeling combustion characteristics in a model oxygen-methane combustion chamber of a liquid rocket engine. The key components of the unit, i.e., the mixing head of the combustion chamber and the regeneratively cooled nozzle, were manufactured using advanced methods of additive manufacturing. The paper emphasizes the specific character of the combustion chamber components made with the use of additive technology and introduces hot-fire test results of the model combustion chamber as part of the experimental unit. The study shows the durability of the mixing head and combustion chamber nozzle under hot-fire test conditions, as well as the reliable operation of the experimental unit as a whole, which confirms the selected design and technological solutions. Within the study, we analyzed the cooling system of the experimental unit for the test conditions, estimated the thermal state of the nozzle, with account for the features of the additively manufactured cooling path. To increase the cooling system’s reliability and expand the combustion chamber pressure application, it is recommended to apply a heat-shielding coating on the firewall of the nozzle. Using new experimental data, we analyzed the parameters of improving the efficiency of the model combustion chamber with the additively manufactured components and corresponding in scale and consumption characteristics to the combustion chamber of the liquid rocket engine

Multiobjective optimization of the cooling system of a marine diesel engine

AbstractAn intelligent cooling system directly influences the thermal load of high‐temperature components, heat distribution, and fuel economy of a diesel engine. An optimal coolant pump rotational speed map is a key factor in intelligent cooling control strategies. In this study, we designed an experimental variable coolant flow system for a maritime diesel engine. Experiment design and D‐optimal designs were used to optimize the parameters of the diesel engine cooling system. The diesel engine speed, load, and freshwater rotational pump speed were selected as variables. The temperature of the high‐thermal‐load zone of the combustion chamber components, fuel consumption rate, effective power, and peak cylinder pressure were selected as response variables, and the D‐optimal method was used to sample the experimental points. Polynomial response surface models were obtained using a stepwise algorithm. A multiobjective optimization problem was converted into a simple‐objective optimization problem using the ideal point method. A genetic algorithm was used to optimize the single‐objective function globally to obtain the optimal freshwater pump speed map for a diesel engine under all conditions. On average, the optimized cooling system decreased the fuel consumption by 1.901%. Six typical propulsive conditions were selected to confirm the validity of the optimization results. The experimental results indicate that the fuel consumption decreased by 2.35%, the effective power increased by 2.26%, and the power consumption of the water pump decreased by 17.83%. The combination of experiment design and D‐optimal designs offers the advantages of low cost, high efficiency, and high precision in solving multiobjective optimization problems involving strong coupling and nonlinear systems. The results of this research provide data support and a theoretical basis for intelligent cooling control strategies.

Turbofan engine performances from aviation, thermodynamic and environmental perspectives

In this paper, JT15D turbofan engine and its main subcomponents are assessed with the aviation, energy, exergy, environmental, and sustainability analyses. In the first stage, the system's specific thrust and specific fuel consumption of the engine are found as 315.9 N s/kg and 15.8 g/kN.s, respectively. Then, system's energetic efficiency is estimated as 21.15% and exergetic efficiency is accounted to be 19.919%. The system's exergetic improvement potential rate, productivity lack ratio and fuel exergy waste ratio are determined as 1573.535 kW, 402.024% and 80.081%, respectively. The ecological and environmental effect factors of the turbofan system are computed to be 5.020 and 4.020, respectively, while the sustainable efficiency factor and exergetic sustainability index rates are found as 1.249 and 0.249, respectively. Finally, among the system parts, the Combustion Chamber (CC) has minimum rates of sustainable efficiency factor, exergetic efficiency and sustainability index, while it has utmost rates of ecological and environmental effect factors, fuel exergy waste ratio, irreversibility and productivity lack ratios. As a general conclusion, the combustion chamber and low pressure compressor components should be optimized for better performance of the system.

The analysis of the thermal barrier coating using Ansys software

The main source of energy for the propulsion of automotive and trucks is still internal combustion piston engines. These are constantly improved in such a way as to achieve the lowest possible consumption of low-emission fuel. The results of the simulation of new technologies are confirmed in experimental stands, thus being the basis for the development of internal combustion engines. This paper shows the theoretical simulation of temperature distribution and thermal flow distribution when a thermal barrier is applied to the engine combustion chamber components. More specifically, the impact of thermal barriers on the surface of the piston crown shall be investigated.

Модифицированный квазистационарный метод изучения изменения температур перехода поршней дизельного двигателя, покрытых теплозащитными материалами

The purpose of the work is to identify complex transient heat flow paths in the combustion chamber of engine, significantly improve the models of diesel engine heat flow, and study the effect of aluminum oxide coating by the galvanic plasma method on short-term and long-term reactions of the piston head. The analysis of operation of aluminum alloy coated diesel engine piston is carried out using a modified quasi -steady method and a finite element method. A thermodynamic analysis is presented using energy and state equations with corresponding gas heat transfer. Time-dependent boundary conditions are set on the gas-blown surfaces of 2D finite element transition models of combustion chamber components. It is shown that this methodology can reveal complex transient paths of the heat flow in engine combustion chambers and distribution details of heat losses in various cooling media. Numerical simulation has shown that the maximum temperature increase relative to the uncoated piston is 64.3% for the coating thickness of 0.13 mm. Tests have shown that the coatings can endure up to 280 thermal cycles. It is found out that predictions of numerical simulation are in good agreement with the results of experiments conducted with repaired pistons. The experimental operation of Cummins КТА 38 engines at Chernogorsk and Vostochno-Beysk coal mines has shown that the engine equipped after repair with the piston coated with aluminum applied by the galvanic plasma method has been in operation for 2 years and 3 months, whereas its set overhaul period is 18,000 hours. Therefore, the proposed methodology allows to reduce temperature variations in the piston and, thereby increase the service life of engine pistons coated with the use of the thermal barrier coating technology.

Comprehensive study of engine characteristics of novel biodiesel from curry leaf (Murraya koenigii) oil in ceramic layered diesel engine

In this study, renewable alternative fuel was produced from curry leaf (Murraya koenigii) oil using transesterification technique in the presence of catalyst along with alcohol. The important properties of produced biodiesel were explored in accordance with ASTM and further chemical compositions were explored by means of FTIR and GC–MS analyses. Four different fuel blends like B25, B50, B75 and B100 were developed. To enhance the study, combustion chamber components were transferred into low heat rejection unit by employing thermal barrier coating with Yttria stabilized zirconia. TBC was achieved by means of atmospheric plasma spray coating technique. The engine used for present work was a fully computerized diesel engine with direct injection technique. In coated engine, B25 showed 0.49% of increased thermal efficiency with 0.015 kg/kWh of decreased fuel consumption. Lower tail pipe emissions like carbon monoxide, hydrocarbon and smoke (except NOx) were noticed in ceramic layered engine than uncoated engine. B25 showed improved engine combustion characteristics like combustion chamber pressure, heat release rate and mean gas temperature in ceramic layered condition owing to short ignition delay, elevated combustion temperature, improved turbulence and oxygen presence in the fuel. On the whole, B25 blend experienced more favouring engine characteristics coated engine and B25 with engine modification technique may be recommended as a promising renewable alternative fuel for conventional diesel with minimum blending condition.

Experimental investigation of pomegranate oil methyl ester in ceramic coated engine at different operating condition in direct injection diesel engine with energy and exergy analysis

The present work give emphasis to investigate the exergy and energy analysis of 20% pomegranate seed oil methyl ester with engine operating parameters modification at thermally coated engine. The present work intends to find the optimum engine operating parameters in ceramic coated diesel engine. The engine was initiated with diesel as a working fuel. Followed by, the conventional engine was allowed to work with pomegranate seed oil methyl ester at standard compression ratio, injection timing and injection pressure. The engine operating conditions were altered in 5.2 kW, 1500 rpm, single cylinder water-cooled direct injection engine. In order to utilize the available heat energy, the combustion chamber components were coated with Yttria Stabilized Zirconia. An attempt has been made to use biodiesel sample at varying compression ratio, injection pressure and injection timing by retarding and advancing the standard condition in both conventional engine and thermal barrier coated engine. The variables determined were energy and exergy prospective of cooling water, combustion, fuel input, performance, shaft work and emission characteristics and second law efficiency. From the results, it was observed that the biodiesel sample showed significant engine characteristics at high compression ratio, injection pressure and injection timing in thermally coated engine. In addition, the aforesaid combination offered a considerable performance in thermodynamic analysis of biodiesel sample in both conventional engine and thermal barrier coated engine. The practice of using pomegranate seed oil methyl ester (B20) with engine operating parameters modification in Yttria Stabilized Zirconia coated engine may be considered as the advantageous approach to achieve better engine characteristics.