Indirect Injection Diesel Engine Research Articles

Performance optimisation of an irreversible dual cycle with respect to pressure ratio and temperature ratio––experimental results of a ceramic coated IDI Diesel engine

An irreversible dual cycle analysis has been performed. Optimisation of the cycle has been performed for power and thermal efficiency with respect to pressure ratio and temperature ratio. Optimum values of pressure ratio and cut-off ratio of the dual cycle, depending on temperature ratios, have been derived analytically and compared with the results of an experimental study of a low heat rejection indirect injection Diesel engine, whose optimum performance was obtained by retarding the injection timing related to the temperature increase in the combustion chamber. Injection timing was retarded from 38 crank angle (CA) to 32 CA. Optimum performance was obtained at 34 CA. At this injection timing, in comparison to the standard Diesel engine, the decrease in the specific fuel consumption and the increase in the brake thermal efficiency were about 6% and 2%, respectively.

An experimental investigation of the effect of the injection pressure on engine performance and exhaust emission in indirect injection diesel engines

Injection spray pressures in diesel engines play an important role for engine performance and emissions obtaining treatment of combustion. In present diesel engines such as common rail engine injection, the pressures can be increased about 1500–2000 bar. In this experimental study, effects of injection pressure on engine performance and exhaust emissions have been investigated. Experiments have been performed on a turbocharger diesel engine with 4-cylinder, 4-stroke, indirect injection. Emissions and engine performance values such as torque, power, break main effective pressure, specific fuel consumption, and fuel flow have been measured both full and part loads by changing injection pressure from 100 to 250 bar and for different throttle positions. According to results, maximum performance has been obtained at 150 bar. In addition, high injection pressure for O 2, SO 2, and CO 2, low injection pressure for NO x , and smoke level must be preferred for decreasing emissions. Results have been given as graphics.

Exhaust emission and combustion evaluation of coconut oil-powered indirect injection diesel engine

This paper presents the results of experimental work carried out to evaluate the exhaust emissions characteristics of ordinary Malaysian coconut oil (COCO) blended with conventional diesel oil (OD) fueled in a diesel engine. This project complies with Malaysian Government strategy on biofuel research activity. The results showed that the addition of 30% COCO with OD produced higher brake power and net heat release rate with a net reduction in exhaust emissions such as HC, NOx, CO, smoke and polycyclic aromatic hydrocarbon (PAH). Above 30% COCO blends, such as 40 and 50% COCO blends, developed lower brake power and net heat release rate were noted due to the fuels lower calorific value; nevertheless, reduced emissions were still noted.

Combustion of jojoba methyl ester in an indirect injection diesel engine

An experimental investigation has been carried out to examine for the first time the performance and combustion noise of an indirect injection diesel engine running with new fuel derived from pure jojoba oil, jojoba methyl ester, and its blends with gas oil. A Ricardo E6 compression swirl diesel engine was fully instrumented for the measurement of combustion pressure and its rise rate and other operating parameters. Test parameters included the percentage of jojoba methyl ester in the blend, engine speed, load, injection timing and engine compression ratio. Results showed that the new fuel derived from jojoba is generally comparable and good replacement to gas oil in diesel engine at most engine operating conditions, in terms of performance parameters and combustion noise produced.

Effect of comprex supercharging on diesel emissions

Diesel engine emissions are highly complex mixtures. They consist of a wide range of organic and inorganic compounds distributed among the gaseous and particulate phases. Particulates and NO x emissions are the important components of the Diesel exhaust. The composition of Diesel exhaust varies considerably, depending on engine type, operating conditions, fuel, and lubricating oil. In this research, the effects of supercharging, which is one of the engine operational parameters, on Diesel emissions have been investigated. For this purpose, a comprex, CX (pressure wave supercharger) was designed and manufactured and then matched to an indirect injection Diesel engine. During the engine tests, the emission parameters (CO, SO x , NO x and smoke density) have been observed and measured for different pulley ratios at full load conditions. The results showed that CX supercharging may be an alternative way of NO x reduction with some modifications.

Performance and exhaust emission characteristics of a lower compression ratio LHR Diesel engine

In this study, the effects of reducing the compression ratio on the performance and exhaust emissions in a low heat rejection (LHR) indirect injection Diesel engine have been experimentally compared to those obtained from a standard Diesel engine (SDE) with fixed compression ratio. Reducing the compression ratio in a SDE without making any modification in the combustion chamber geometry and improvements in fuel properties cause the ignition delay time to be unduly long, and consequently, an unacceptable pressure rise is experienced. By means of high temperature increases in the combustion chamber of the LHR Diesel engine, the compression ratio was lowered from 18.20 to 16.10 in 0.7 intervals. Satisfactory performance was obtained at compression ratios of 17.50 and 16.80 in the LHR engine. In comparison to the SDE, at these compression ratios, the specific fuel consumption and NO x emissions are, respectively, decreased about 2.9% and 15%.

A study on effects of recirculated exhaust gas upon wear of cylinder liner and piston in diesel engines

The effects of recirculated exhaust gas on the wear of cylinder liner and piston were experimentally investigated by a two-cylinder, four cycle, indirect injection diesel engine operating at 75% load and 1600 rpm. For the purpose of comparison between the wear rates of the two cylinders with and without EGR, the recirculated exhaust gas was sucked into one of two cylinders after the soot in exhaust emissions was removed by an intentionally designed cylinder-type scrubber equipped with 6 water injectors (A water injector has 144 nozzles of mm diameter), while only the fresh air was inhaled into the other cylinder. These experiments were carried out with the fuel injection timing fixed at 15.3° BTDC. It was found that the mean wear rate of cylinder liner with EGR was greater in the measurement positions of the second half than those of the first half, that the mean wear rate without EGR was almost uniform regardless of measurement positions, and that the wear rate of piston skirt with EGR increased a little bit, but the piston head diameter increased, rather than decreased, owing to soot adhesion and erosion wear, and especially larger with EGR.

Effects of diesel/water emulsion on heat flow and thermal loading in a precombustion chamber diesel engine

An experimental investigation has been carried out to study the effects of using water/diesel emulsion fuel in an indirect injection diesel engine on the heat flux crossing liner and cylinder head, thermal loading and metal temperature distribution. A single cylinder precombustion chamber diesel engine has been used in the present work. The engine was instrumented for performance, metal temperature and heat flux measurements. The pure gas oil fuel and different ratios of water/diesel emulsion were used and their effects on the heat flux level and the injector tip temperature are studied. Two correlation were found for the heat flux crossing the liner and the cylinder head at various water/diesel emulsion ratios, fuelling rate and thermocouple probe locations. It was found that the addition of water to diesel fuel, to control the nitrogen oxides emissions, has great influence on reducing the heat flux, the metal temperatures and thermal loading of combustion chamber components.

Performance, emissions and wear characteristics of an indirect injection diesel engine using coconut oil blended fuel

Dynamometer tests have been carried out to evaluate the performance, emissions and wear characteristics of an indirect injection diesel engine when fuelled by 10, 20, 30, 40 and 50 per cent blends of ordinary coconut oil (COCO) with ordinary diesel fuel (OD). The test was conducted for 100 h using each of the test fuels to monitor the effect of COCO blends on the wear and lubricating oil performance. OD fuel was also used for comparison purposes. The operating performance of the engine and the emission characteristics of exhaust gases were compared. The effect of blended fuel on the engin's wear and lubrication characteristics in terms of wear metal (Fe), water concentration, oxidation, viscosity, total base number and additive depletion was analysed. The performance and emissions characteristics results showed that 10-30 per cent coconut oil blends produced slightly higher performance in terms of brake power than OD. All the COCO blends produced lower exhaust emissions including polycyclic aromatic hydrocarbons and particulate matter. The wear and lubrication oil characteristics results showed that COCO blends up to 30 per cent produced similar results to OD. This programme will give useful information for further research and development in the future if COCO is used as an alternative to OD.

Particulate matter size distribution and associated polycyclic aromatic hydrocarbon content from indirect and direct injection diesel engines

Within the framework of atmospheric aerosol study, evaluation of the contribution of the particle source to global atmospheric pollution is a challenge that requires an improvement in the knowledge of particulate matter. As a part of this knowledge improvement, this study has been focused on particles emitted from diesel vehicles. Two light-duty diesel vehicles were studied for particulate matter size distribution and associated polycyclic aromatic hydrocarbon (PAH) content. A diffusional and inertial spectrometer was used, allowing particles from 7.5 nm to 15 μm to be collected and analysed. Teflon-coated glass fibre filters were employed as collector substrates, and weighed prior to and after sampling. Each of them was extracted with methylene chloride in an accelerated solvent extractor, cleaned on a silica gel micro-column and analysed for PAH by gas chromatography/mass spectrometry using internal standards for quantitation. Both analytical and sampling methods were validated. The highest particle mass was found to be emitted at 0.2 μm for the direct injection engine and 0.07 μm for the indirect injection engine. PAHs were found to be essentially distributed on particles in the accumulation mode, at about 0.2 μm, and high molecular weight PAH distributions were found to be bimodal or trimodal, depending on the engine injection.

Performance and Combustion Characteristics in a Methanol-Fueled IDI Engine.

Restraining the initial combustion, promoting the diffused combustion and reducing the cyclic combustion variation are of utmost importance to improving the fuel economy, exhaust gas emissions, and noise of the methanol fueled indirect injection (IDI) diesel engine. The author closely studied methanol fuel combustion in a high speed diesel engine (swirl-chamber system and single cylinder of 82.5mm bore and 92mm stroke), using different ignition systems, such as the spark-assisted method, glow-assisted method, and diesel fuel pilot injected method, to evaluate the engine performance and combustion characteristics. The methanol-fueled engine used in the study had a new combustion chamber with a refined jet passage for the optimum air discharge coefficient as well as for improved diffusion and penetration of jet in the main chamber. The engine cylinder was equipped with a miniature throttle nozzle for improved fuel injection characteristics. The new methanol-fueled combustion system was found to outperform the diesel-fueled conventional combustion system as regard the fuel consumption, smoke emission, and NOx emissions, regardless of which ignition system were employed.

Evaluating waste vegetable oils as a diesel fuel

The research into turning a vegetable oil into an alternative fuel has been underway for some time [1-5]. Although some countries have begun to use some biomass as a fuel for the automobile, the wide use of an alternative fuel has been difficult without substantial subsidies owing to the cost of the biomass which is 3-5 times higher than that of fossil fuel. However, the cost of waste vegetable oil is competitive with that of fossil fuel and, in the collection of waste vegetable oil, there is an additional advantage of being able to prevent its illegal dumping. Furthermore, the reuse of the oil will improve the profitability of its collection. This research focused on the engine performance and emission characteristics of methyl-esterified vegetable oil when it is used in a diesel engine of an automobile. The research conducted with direct injection (DI) and indirect injection (IDI) diesel engines revealed that, for engine performance, the alternative fuel was on a par with light oil. For the emission of particulates, with the IDI diesel engine there was no significant difference between the light oil; however, the DI engine proved to emit a much larger quantity of particulates in the low to middle load range. The research also revealed the necessity for countermeasures against solidification of the fuel during the winter months, the generation and emission of aldehyde and benzene, which are typical of oxygenated fuel, and the tempuralike smell caused by propionaldehyde.

A Study on the Effect of Recirculated Exhaust Gas with Scrubber EGR System upon Exhaust Emissions in Diesel Engines

The effects of recirculated exhaust gas on the characteristics of and soot emissions under a wide range of engine load have been experimentally investigated by a water-cooled, four-cylinder, indirect injection, four cycle and marine diesel engine operating at two kinds of engine speeds. The simultaneous control of and soot emissions in diesel engines is targeted in this study. The EGR system is used to reduce emissions, and a novel diesel soot removal device with a cylinder-type scrubber for the experiment system which has 6 water injectors(A water injector has 144 nozzles in 1.0 mm diameter) is specially designed and manufactured to reduce the soot contents in the recirculated exhaust gas to intake system of the engines. The intake oxygen concentration and the mean equivalence ratio calculated by the intake air flow and fuel consumption rate, and the exhaust oxygen concentration measured are used to analyse and discuss the influences of EGR rate on and soot emissions. The experiments are performed at the fixed fuel injection timing of BTDC regardless of experimental conditions. It is found that emissions are decreased and soot emissions are increased owing to the drop of intake oxygen concentration and exhaust oxygen concentration, and the rise of equivalence ratio as the EGR rate rises.

Effect of pilot fuel quantity on the performance of a dual fuel engine

It is well known that the operation of dual fuel engines at lower loads suffers from lower thermal efficiency and higher unburned percentages of fuel. To rectify this problem, tests have been conducted on a special single cylinder compression ignition research engine (Ricardo E6) to investigate the effect of pilot fuel quantity on the performance of an indirect injection diesel engine fuelled with gaseous fuel. Diesel fuel was used as the pilot fuel and methane or propane was used as the main fuel which was inducted into the intake manifold to mix with the intake air. Through experimental investigations, it is shown that, the low efficiency and excess emissions at light loads can be improved significantly by increasing the amount of pilot fuel, while increasing the amount of pilot fuel at high loads led to early knocking.

The Effects of Thermal Barrier Coatings on Diesel Engine Emissions

This study has characterized the influence of thermal barrier coatings (TBCs) applied to combustion chamber surfaces on the emissions from an indirect injection (IDI) diesel engine. The TBCs were applied to the piston crown, the cylinder head (fire deck) and the valves of a single cylinder Yanmar TS-180 IDI diesel utility engine. The gaseous and particulate emissions from the baseline (uncoated) and ceramic-coated engine were analyzed to assess the changes in the combustion process caused by the coatings. The results of these analyses show two clear trends during operation of the baseline and ceramic-coated engine. First, comparison of the emissions from the four modes of operation for the baseline (uncoated) engine shows that particulate matter emissions (on a g/kWh basis) are highest at low load-low speed (mode 4) conditions. At low load-low speed conditions (modes 3 and 4), particulate matter decreases substantially with the TBCs present. Second, these observations combined with thermal and morphological analyses of the particulate matter show that the TBCs reduce particulate mass by reducing the volatile organic content of the particulate.

Organic emissions profile for a light-duty diesel vehicle

In this report we describe the speciated gas-phase hydrocarbon and carbonyl emissions as collected from a recent model automobile powered by a 2.5ℓ indirect injection diesel engine and outfitted with a production oxidation catalyst for exhaust after-treatment. The vehicle was run on a typical low sulfur (500 ppm S) European diesel fuel and measurements were made over the European MVEG test cycle. The diluted tailpipe emissions were sampled for light hydrocarbons (C 1C 12) using Tedlar bags and semi-volatile hydrocarbons (C 12C 20+) using Tenax cartridges. Both the light and semi-volatile hydrocarbon fractions were speciated using capillary gas chromatography. Combining the two sets of speciation data provided a profile of the gas-phase hydrocarbon emissions from a light duty diesel vehicle. Of the total gas phase non-methane hydrocarbons emitted, 80% were accounted for in the light hydrocarbon fraction, and 20% in the semi-volatile fraction. The semi-volatile fraction, which extended only to about C 15, was composed almost entirely of unburned fuel molecules, but with enrichment of the aromatic species relative to the fuel itself. n-Alkanes (paraffins) and methylnaphthalenes accounted for approximately 37% of the semi-volatile fraction. Aldehydes and ketones represented 34% of NMOG. Formaldehyde and acetaldehyde, account for 74% of the total carbonyl emissions.

Influence of the resonant frequency on the control of knock in diesel engines

This paper presents an alternative approach to investigating the origin and the development process of knock vibrations that occur in an indirect injection (IDI) diesel engine. In contrast to the conventional analysis of the pressure rise rate, this study focuses on the analysis of instantaneous resonant frequencies at different moments during combustion. The smoothed pseudo-Wigner-Ville distribution (SPWVD) and Hilbert transform methods are applied to estimate the resonant frequency under different conditions representing various knock intensities. Two important factors are found significantly to influence knock development. Finally, design strategies and preferable fuel injection patterns are suggested for reducing knock intensity.

Combustion of simulated biogas in a dual-fuel diesel engine

Technology related to biogas has been steadily developed over the last 50 years from small individually designed units to larger production plants. The development, however, has largely taken place on the side of biogas production and anaerobic waste treatment. Utilization of the gas produced by these methods has only recently been the subject of more scientific evaluation. The transformation of energy through biogas into the thermodynamically higher valued mechanical energy successfully and economically is now the most important research area in this field.Of the engine work already published, most concerns spark-ignited engines. The authors’ research work concerns the use of biogas in dual-fuel diesel engines. It examines engine performance using simulated biogas of varying quality representing the range of methane:carbon dioxide composition which may be encountered in gas from different sources. The total programme includes the effects of biogas quality and of the proportion of energy from pilot fuel injection over a range of speeds and loads, investigations into the performance parameters over a range of compositions of gaseous mixture. A two-cylinder, indirect-injection diesel engine of stationary type is being used as the first experimental test bed in this work and the variation of quality is provided by mixing natural gas and carbon dioxide. A data acquisition system for in-cylinder pressure and crank angle is being used successfully and some emissions measurements are also available, particularly for CO and O2.One of the authors is from India where there is thought to be considerable potential for exploiting the gaseous products from resources such as biogas, landfill and sewage gas through small stationary dual-fuel engines for irrigation and CHP applications. The nature of combustion process in the dual-fuel engine is examined by the authors through pressure-crank angle data and studies of characteristics affecting engine efficiency.

An experimental investigation of flow parameters inside a spherical swirl pre-chamber of a diesel engine under motoring condition

The main aim of the present investigation is to experimentally study the flow parameters inside a spherical combustion chamber of an indirect injection diesel engine. For this a spherical chamber has been fitted in the cylinder head. Using a constant temperature hot-wire anemometer, measurements have been made under non-firing condition at 400 and 500 rpm during compression stroke. Mean velocity and turbulence intensity values are evaluated from the hot-wire signal. Measurements are made at three axial planes, six angular locations and four radial positions. Large variations of mean velocity and turbulence intensity have been observed within the chamber. From the measurements, the mean velocity and turbulence intensity are found to be maximum at 30° before compression TDC and these values are found to decrease towards the centre of the pre-chamber. The mean velocity and turbulence intensity distribution with respect to various locations and crank angles are presented and discussed.

Experimental and simulation analysis of the transient operation of a turbocharged multi-cylinder IDI diesel engine

SUMMARY An experimental and theoretical analysis is carried out to study the response of a multi-cylinder, turbocharged, IDI (indirect injection) compression ignition engine, under transient operating conditions. To this aim, a comprehensive digital computer model is developed which solves the governing di⁄erential equations individually for each cylinder, providing thus increased accuracy over previous ‘single-cylinder’ simulations. Special attention has been paid for diversifying the transient operation from the steady-state one, providing improved or even new relations concerning combustion, heat transfer to the cylinder walls, friction, turbocharger and aftercooler operation, and dynamic analysis for the transient case. An extended steady state and transient experimental work is conducted on a specially developed engine test bed configuration, located at the authors’ laboratory, which is connected to a high-speed data acquisition and processing system. The steady-state measurements are used for the calibration of the individual submodel constants. The transient investigation includes both speed and load changes operating schedules. During each transient test four major measurements are continuously made, i.e. engine speed, fuel pump rack position, main chamber pressure and turbocharger compressor boost pressure. The hydraulic brake coupled to the engine possesses a high mass moment of inertia and long nonlinear load-change times, which together with the indirect injection nature of the engine are important challenges for the simulation code. Explicit multiple diagrams are given to describe the engine and turbocharger transient behaviour including smoke predictions. The agreement between experimental and predicted responses is satisfactory, for all the cases examined, proving the validity of the simulation process, while providing useful information for the engine response under various transient operations. ( 1998 John Wiley & Sons, Ltd.