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This paper presents a hydraulic pump fault diagnosis method based on a discharge pressure pulsation model. This diagnosis method was based on the pressure signals measured at the discharge port of the pump. The obtained signals were transformed into frequency domain for performing wavelet analysis to separate the fault signals from the pressure signal at the time a fault occurs. This method was first evaluated via simulation analysis, and then validated against test data. Results showed that this wavelet based fault diagnosis method was capable of detecting pump failure using the outlet pressure pulsating signal.

Wavelet analysis was used to calculate turbulence and mean velocity levels for LDV measurements made in a four valve spark ignition engine. Five different camshafts were tested, and they produce significantly different flow behaviour. The standard cam gives tumble and with valve deactivation, swirl is produced. One camshaft with early inlet valve closing and two camshafts with late inlet valve closing were also tested. The wavelet toolbox for Matlab version 5.1 has been used for the wavelet calculations. The wavelet technique produces both time resolved and frequency resolved velocity information. The results indicate some influence of the turbulence frequency content on the rate of heat release. Correlation against heat-release can be seen for different scales of turbulence. The breakdown of the tumble (low frequency turbulence) into high frequency turbulence can be seen clearly.

Recent advancements in the combustion control of new generation engines can benefit from real time, precise sensing of the cylinder pressure profile to facilitate successful combustion feedback. Currently, even laboratory-grade pressure sensors can deliver pressure traces with insufficient signal-to-noise quality due to electrical or combustion-induced signal interference. Consequently, for example, calculation of compression and expansion polytropic indices may require statistical averaging over several cycles to deliver required information. This lag in the resultant feedback may become a concern when the calculated combustion metric is used for feedback control, especially in the case of transients. The method described in this paper involves a special digital filter offering excellent performance which facilitates reduced-error calculation of individual polytropic indices.

Wavelet transform analysis is capable of revealing aspects of data that other techniques miss such aspects are trends, and discontinuities in higher derivates. This method can often compress or de-noise a signal without any appreciable degradation and it provides accurate information on the localization of energy content in time and frequency [1]. The Wavelet transform method has been applied to the analysis of combustion noise and piston slap in order to identify the effects on the engine structure vibration. The experimental results showed that combustion noise and piston slap were successfully detected from the acceleration signals picked up by external transducers in the outer wall of an in-line, 6 cylinder diesel engine.

The paper covers highlights of SAE activity on emissions control from the early efforts of Campbell and others in the 1930's to the present time. Evidence of substantial involvement in the Los Angeles “smog” composition led to the development of analytical tools for continuous evaluation of exhaust. With these tools and other basic information, it became possible to develop many control devices. Over 20 of these devices have been added as standards have tightened. The negative result has been increasing cost and complexity. The crankcase and evaporative systems have been controlled, but the principal emissions have come from the exhaust, and therefore most of the controls were directed to this source. Combustion within the engine has been the principal area of attention, but when this did not meet the requirements of the existing statues, combustion beyond the exhaust ports became important. Notable contributions to this art were air pumps, afterburners and catalysts.

Karanja biodiesel is prepared using Karanja oil and methanol by the process of transesterification. Use of Karanja oil methyl ester (KOME) in a 780 hp CIDI military engine was found to be a highly compatible alternative fuel with low emission characteristics. Engine was operated for 100 hours each using pure karanja biodiesel and mineral diesel fuel, respectively. These were subjected to long-term endurance tests. Lubricating oil samples, drawn from both fuelled engine after a fixed interval of 20 hours, were subjected to elemental analysis. Atomic absorption spectroscopy (AAS) was done for quantification of various metal debris concentrations. Wear metals were found lower for a biodiesel operated engine system. Lubricating oil samples were also subjected to ferrography indicating lower wear debris concentrations for a biodiesel-operated engine. Scanning electron microscopy was also conducted on the cylinder liner surfaces exposed to wear.

Since wear is a not a material property, but a tribological system property, it is of great importance to know the wear, friction and lubrication behavior of materials tested in bench equipment. This work presents reciprocating pin-on-plate bench tests results, with gas nitrided stainless steel pins and gray cast iron plates. The testing conditions were 0.5 and 3.2 Hz frequency, 20 and 600N applied load and 100 and 150 °C. Under these conditions, mild to severe wear transition was observed. It was noticed noise emission changes at wear transition. This noise change could be used to verify wear transition mechanism.

Three pairs of cars were each driven over 80 000 km at predominantly highway speeds and summer ambient temperatures. One car of each pair used an SAE 0W-30 partial-synthetic motor oil, and the other used an SAE 10W-30 all-mineral motor oil. These oils were of similar chemistry. The test has demonstrated that the low viscosity, SAE 0W-30 oil offered comparable performance to the SAE 10W-30 oil, in terms of engine wear and cleanliness. Excellent connecting rod and main bearing wear, and valve train wear protection was observed for both oils, even though their viscometric properties at high temperatures and under high shear rate conditions are less than the minimum proposed by some engine manufacturers and researchers.

SEVEN HUNDRED tons of iron, estimated by the authors to be worn annually from the cylinder bores of American automotive engines, cause an annual engine repair bill believed to exceed $1,000,000,000. A large part of this wear is due to corrosion, particularly in severe service such as gasoline-powered delivery vehicles or stationary diesel installations. Test results indicate that wear rates can be materially reduced by the use of crankcase lubricating oils containing high concentrations of alkalinity. The authors also present examples of radiochemistry research. Radiotracers are used to prove that oil consumed by the engine carries with it the iron debris which it contained at the moment of consumption.

Automobile component particularly the engine cylinder is subjected to continuous wear during the running of the automobile specifically the two wheelers. Aluminium alloys are the material of choice due to their high strength/weight ratio. As aluminium alloys have poor wear and corrosion resistance, a uniform wear resistant composite coating is required on the bore of the internal combustion engine cylinder. There are several methods to produce composite coatings like chemical and physical vapour deposition, plasma spraying, metal infiltration, powder metallurgy etc. Ni-SiC coating commercially known as NIKASIL, is the most commercially used coating in automobile’s/aero IC engines. However, SiC tends to react with the nickel matrix at temperatures above 400 °C forming a brittle nickel silicide which deteriorates the performance of the coating. Also, the synthesis of SiC particles utilizes high energy.

Sliding wear of magnesium (Mg) engine cylinder bore surfaces and corrosion of Mg engine coolant channels are the two unsolved critical issues that automakers have to deal with in development of magnesium-intensive engines. In this paper, Plasma Electrolytic Oxidation (PEO) process was used to produce oxide coatings on AJ62 Mg alloy to provide wear and corrosion protection. In order to optimize the PEO process, orthogonal experiments were conducted to investigate the effect of PEO process parameters on the wear properties of PEO coatings. The PEO coatings showed a much better wear resistance, as well as a smaller friction coefficient, than the AJ62 substrate. The galvanic corrosion property of AJ62 Mg coupled with stainless steel and aluminum (Al) was investigated via immersion corrosion test in an engine coolant. Applying PEO coating on Mg can effectively prevent the galvanic corrosion attack to Mg.

The characteristic wear of electroplated chromium on piston rings has changed over the past 15 years. The reasons for the change are discussed and a theory proposed for the wear mechanism. The theory is supported by engine test results, radioactive ring and cylinder studies, and metallographic exhibits.

A new bench tester for laboratory simulation of piston ring and cylinder wear has been developed. Tests are made using liner segments which bear against a reciprocating piston ring. Temperatures up to 550°C, and loads and speeds representative of the most severe top ring conditions may be imposed. A precision oil spray system delivers the desired quantity and quality of oil to the wear interface. The computer controlled simulator duplicates the desired test cycle, and displays and stores data on friction forces and friction coefficients as the test proceeds. In this paper results are presented from the simulator for production and prototype ring and liner combinations, including ceramic coatings for potential use in advanced diesel engines. The importance of the method of oil delivery on test repeatability is emphasized. Some comparisons with Cameron Plint bench tests and firing engine results are presented.

We assessed the feasibility of weight reduction concerning noise and vibration characteristics for engine components. Three alternatives were plastic intake manifold, stamped steel oil pan, and no balance shaft. The assessment indices were engine noise level, engine mount bracket vibration, and engine block vibration. Reducing the reciprocating mass and applying design alternatives made the removal of balance shaft feasible. The lightweight plastic intake manifold was beneficial to the engine vibration with a little improvement to the engine noise. The stamped steel oil pan, with optimal structural ribs design and EMS calibration, offered all the benefits of weight, vibration, and noise improvements.

The weight reduction and noise refinement of powertrain has been major concern in automotive industry although they are known as self trade-off. This paper presents various methods to deal with those problems for new Hyundai 1.5 liter powertrain. It was possible to reduce the weight of powertrain by using plastic for both headcover and intake manifold, aluminum for crankshaft damper pulley and stainless steel for exhaust manifold and by reducing the general thickness of cylinder block On the other hand, the noise refinement of vibration in the powertrain was made by optimizing the engine structure and by adapting the hydraulic lash adjuster valve train system, which was proved to be effective in mechanical noise of engine.

Recently, further weight reduction of the car components are demanded for the purpose of fuel-efficient. In particular, the weight reduction of moving parts such as the connecting rod is indispensable for the weight reduction of neighboring parts. The lightweight connecting rod can be accomplished by decrease in cross section of rod part by using high strength steel. However, conventional high strength steel has bad machinability. Therefore, we developed a new high strength steel for connecting rod. The developed steel is based on middle carbon microalloyed steel, and vanadium content is increased to obtain the high yield ratio. As a result, strength of developed steel is 10% higher than the conventional steel. And a weight of new connecting rod can be reduced 8% by using developed steel. This connecting rod had been mass-produced for automobile engine from 2013.

FEM modeling was used to reduce the weight of engine reciprocating parts (pistons and piston pins) in order to reduce engine vibration and aid in the weight reduction of other engine pans. A non-dimensional number using the Mises stress σM /σ0.2 (θ) was used to improve the accuracy of simulation. It was found that changes in piston shape could compensate for increased stress due to reduced piston wall thicknesses, resulting in effective weight reduction for this part. Reduced engine weight not only improves performance but also lowers fuel consumption. This, combined with less engine vibration, leads to a lighter and more efficient vehicle.

In order to improve the fuel economy of automobiles, further increase in the efficiency of gasoline engines is strongly demanded. In particular, reducing the weight of the pistons plays a major role. The pistons in this engine were connected to the connecting rods by a spherical joint bearing instead of a conventional piston pin, and a thin-walled piston top with radial rib structure was employed to reduce the piston weight. To ensure the required piston functions, lubrication of the bearing, cooling of piston top and the skirt design for smooth motion were important challenges to realize weight reduction of the spherical joint piston. In this paper, firstly, the lubrication characteristics of the ball were evaluated using a high frequency fluctuating load device to minimize the diameter of the ball of the spherical bearing. In the next step, cooling of the thin-walled piston top structure by oil fed through the connecting rod was investigated.

This paper describes a conceptual development program to demonstrate the weight and cost reduction potential using steel stampings for internal combustion engines and engine components. Various components have been redesigned as steel stampings to replace cast iron or cast aluminum items on a weight and/or cost reduction basis. Designs of a stamped steel engine block, intake and exhaust manifolds, water pump, power steering pump, pulleys, alternator and turbocharger housing are described. Stamped steel versions which have been prototyped and tested are described. A review of current applications and suggested applications of stampings to replace castings concludes the paper.

In the realm of modern powertrains, the paramount objectives of weight reduction, cost efficiency, and friction optimization drive innovation. By streamlining drive trains through component minimization, the paper introduces a groundbreaking approach: the integration of fuel pump and vacuum pump drive systems into the main camshaft of a two-valve-per-cylinder push-rod actuated 4-cylinder diesel engine. This innovation is poised to concurrently reduce overall weight, lower costs, and minimize drive losses. The proposed integration entails the extension of the camshaft with a tailored slot, accommodating a three-lobed cam composed of advanced materials. This novel camshaft configuration enables the unified propulsion of the oil pump, vacuum pump, fuel pump, and valve train, effectively consolidating functions and components.