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Engine is the most common and important component in all the vehicles. An improved understanding of noise signal is required for the early detection of incipient engine component failure to achieve high reliability. In diesel engine, the combustion noise is so named to distinguish it from the noise of mechanical sources in the engine such as the valve train, fuel injection system and timing gears. On the other hand, piston slap is a combination of combustion and mechanical sources within the engine, and is not straightforward one. However, the aim of the present work is to separate the noise contributions of combustion and mechanical (motored) sources. Moreover, the noise spectra obtained when the engine was in fired condition were used to detect engine events and faults. The noise spectra were predicted based on the vibration velocity measurements, which were taken over the diesel engine surfaces (panels).

In recent years, the development of environmental friendly vehicles, such as electric vehicles and fuel cell vehicles, has further accelerated. Hybrid vehicles with regards to practical application which employ a combination of gasoline engine and electric motor remain one step ahead of the other technologies. On the other hand, as for noise and vibration (NV) phenomena, hybrid vehicles have many different features from those of conventional vehicle. Firstly high frequency noise is generated by the hybrid units, such as motor/generator and power control unit. Secondly low to middle frequency NV phenomenon tends to be worse. However, this paper describes the noise characteristics for HV induction electric motor, where its noise comprises three types namely: electromagnetic, aerodynamic and mechanical. Moreover, the influences of the cooling fans' blades number on both motor aerodynamic and total noise are presented.

All automotive fleets' ownerships want to increase their fleets' availability; therefore, they resort to consider the conventional maintenance policy. Despite of, this policy increases fleets availability but the cost will be high. This is due to replace the parts before the end of their lifetime. On the other hand, this policy is based on time where it is not cost-effective. Consequently, this conventional maintenance policy is not adequate to fulfill the needs of high availability for automotive fleets. However, in this paper the study is directed to condition-based predictive maintenance concept as an alternative policy to determine fleet's health for increasing the fleet availability and to reduce the operating cost. The concept is based on predicting the system degradation and calculating the reliability function for the component. An application carried out on internal combustion engine crankshaft main bearing to illustrate the effectiveness of this technique.

Despite considerable advances in predictive maintenance concepts are still largely reserved for only the most critical system components and have not found their place in mainstream machinery health management. Even though there are a number of condition monitoring and analysis techniques, researchers are in search of a simple and easy way to monitoring the condition of an engine, which is an omnipresent and an important power unit in any vehicle or machinery. Vibrations have been the most recent easy to measure condition monitoring. However, this paper will provide the details of diagnostic technologies that can be applied on a single cylinder diesel engine components, and span a continuum of sophistication and rely upon the availability vibration measurement equipments. The vibration measurements are used as monitoring parameters, while single-processing indices are used for diagnosis procedure.

An approach to the behavioral analysis of the friction material (pad) is presented that is based mainly on the Finite Element Methods representation. This Finite Element Method was used to predict the deformation of the friction material and also the pressure distribution across the contact area with the rotor. The influence of the friction material compressibility, back-plate thickness, backplate stiffness, and the piston diameter were considered. The effect of the piston pressure on the back-plate was also considered to study the behavior of the friction material. The modal analysis of the friction material was also discussed. The results showed that in order to evaluate the design performance of the disc brake, most of the components should be fully design controlled and the distributions of the nodal reaction force may affect the wear happen in the friction material.