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A 3D grid model of engine brake is established for an automobile engine. The dynamic compression release braking process is simulated by using this model. In the process of engine braking, the movement of valve and piston causes changes of the internal flow field of the engine. In this paper, the movement of valve and piston were defined by using the dynamic grid technology, so that the numerical simulation is closer to the actual situation via the updating of grid. Based on the relevant parameters of compression release engine brake (including the opening of the exhaust valve, the engine speed and the exhaust back pressure), the pressure and power of the compression release braking system were simulated under the conditions of multiple operating conditions and experimental verification was carried out. The results showed that the braking works of the compression release engine brake are mainly from the compression stroke and the exhaust stroke.

Hybrid electric vehicles (HEVs) are considered as the most commercial prospects new energy vehicles. Most HEVs have adopted Atkinson cycle engine as the main drive power. Atkinson cycle engine uses late intake valve closing (LIVC) to reduce pumping losses and compression work in part load operation. It can transform more heat energy to mechanical energy, improve engine thermal efficiency and decrease fuel consumption. In this paper, the investigations of Atkinson cycle converted from conventional Otto cycle gasoline engine have been carried out. First of all, high geometry compression ratio (CR) has been optimized through piston redesign from 10.5 to 13 in order to overcome the intrinsic drawback of Atkinson cycle in that combustion performance deteriorates due to the decline in the effective CR. Then, both intake and exhaust cam profile have been redesigned to meet the requirements of Atkinson cycle engine.

A current trend by automotive manufacturers involves the use of Oil Life Monitoring Systems (OLMS) to determine the drain interval of the engine oil. The premise of the OLMS system is to extend the oil drain interval by monitoring engine parameters and reduce the number of oil changes during the vehicle's lifecycle. The OLMS uses an engine oil sensor or various engine sensors and an advanced algorithm to predict when the engine oil has reached the end of its lifecycle. The OLMS effectively supports customer demands for lower operating costs and government fleet requirements to reduce the consumption of petroleum derived products and hazardous waste. This research analyzed the correlation between various external influences that alter the output of the OLMS. The external influences include monitoring of the vehicle operating conditions in densely populated metropolitan statistical areas versus more rural areas.

With its advantages on cost and performance, the integrated exhaust manifold (casting with the turbine) is being used on more vehicles by auto makers. Generally, when compared with the divided exhaust manifold, the integrated exhaust manifold stands for higher vibratory excitation from gas dynamics. In this paper, the gas dynamics excitation has been computed through the GD (gas dynamics) software GT-Power which calculates the exhaust pipe surface pressure, and CFD code Star-CCM+ which calculates the turbine blade force. And the response of manifold has been solved under this excitation. On the other hand, the mechanical excitation has been computed through the MBD (multi-body dynamics) platform AVL-Excite-PU, and the responses under the gas excitation plus the mechanical load have been studied in order to analyze the effects of the fluid excitation on an integrated manifold.

In engine radiated noise analysis, the conventional boundary element method (BEM) is unsuitable for conducting large-scale acoustic simulations because of low calculation efficiency. The Fast Multipole boundary element method (FMBEM), although greatly improved calculation efficiency for large-scale acoustic simulations, has the problem of low efficiency at the low frequency region and low accuracy at the high frequency region. Those methods cannot meet the requirements of design engineers to get the results in a couple of days. In order to solve the powertrain radiated noise problems accurately and efficiently, some simplified methods and scripts were developed in big-three auto makers and suppliers, such as DIRA. Those scripts are very fast and can meet the timing requirement, but generally, without clear physical meaning.

A current trend by automotive manufacturers involves using tires with a lower aspect ratio, while increasing the rim diameter to effectively maintain the same final drive ratio. The use of larger 16- and 17-inch rims in the design of automobiles is dramatically increasing, especially from American and European automotive manufacturers. This trend is responsible for increased vehicle life cycle costs, increased vehicle fuel consumption and increasing waste and consumption of precious resources, all while reducing commonly monitored sustainable fleet deliverables. A measurable burden for a fleet based organization is the additional cost associated with purchasing lower profile tires for larger diameter rims. The use of a lower aspect ratio tire will increase the total output of waste which reduces sustainable goals. In order for a manufacturer to maintain the same final drive ratio with lower aspect ratio tires, it is necessary to use a physically larger rim.

Approximately 500 million oil filters are sold in the United States of America each year, and are not required by law to meet any Government or industry testing procedures prior to being sold in the US market. The lack of required testing has resulted in no uniform testing procedure which in many cases leads to misleading claims by the manufacturer and/or inferior filtration designs and construction materials. Due to the lack of mandatory testing, the majority of oil filter manufacturers use in-house labs with different filtering methods to highlight the filter's unique strengths while not disclosing all relevant filtering data and in turn the filters inherent weaknesses. Instead of manufacturers offering full disclosure of the relevant performance specifications and internal design characteristics of the oil filter, they state that the specifications are proprietary information.