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An accurate bushing model is vital for vehicle dynamic simulation regarding fatigue life prediction. This paper introduces the Advanced Bushing Model (ABM) that was developed in MATLAB® environment, which gives high precision and fast simulation. The ABM is a time-domain model targeting for vehicle durability simulation. It dynamically captures bushing nonlinearities that occur on stiffness, damping and hysteresis, through a time-history-based fitting technique, compensated with frequency dependency functionality. Among the simulated and test-collected bushing loads, good correlations have been achieved for elastomer bushings and hydraulic engine mounts and validated with a random excitation signal. This ABM model has been integrated into a virtual shaker table (from a parallel project) as the engine mount model to simulate the mount load, and has shown acceptable prediction on fatigue damage.

An experimental investigation of low temperature combustion (LTC) cycles is conducted with diesel and ethanol fuels on a high compression ratio (18.2:1), common-rail diesel engine. Two LTC modes are studied; near-TDC injection of diesel with up to 60% exhaust gas recirculation (EGR), and port injected ethanol ignited by direct injection of diesel with moderate EGR (30-45%). Indicated mean effective pressures up to 10 bar in the diesel LTC mode and 17.6 bar in the dual-fuel LTC mode have been realized. While the NOx and smoke emissions are significantly reduced, a thermal efficiency penalty is observed from the test results. In this work, the efficiency penalty is attributed to increased HC and CO emissions and a non-conventional heat release pattern. The influence of heat release phasing, duration, and shape, on the indicated performance is explained with the help of parametric engine cycle simulations.

Polyurethane (PU) foam is used for many automotive applications with the benefits of being lightweight, durable, and resistant to heat and noise. Applications of PU foams are increasing to include non-traditional purposes targeting consumer comfort. An example of this is the use of PU foam between the engine and engine cover of a vehicle for the purpose of noise abatement. This addition will provide a quieter ride for the consumer, however will have associated environmental impacts. The additional weight will cause an increase in fuel consumption and related emissions. More significant impacts may be realized at the end-of-life stage. Recycling PU foams presents several challenges; a lack of market for the recyclate, contamination of the foams, and lack of accessibility for removal of the material.

As a renewable energy source, the ethanol fuel was employed with a diesel fuel in this study to improve the cylinder charge homogeneity for high load operations, targeting on ultra-low nitrogen oxides (NOx) and smoke emissions. A light-duty diesel engine is configured to adapt intake port fuelling of the ethanol fuel while keeping all other original engine components intact. High load experiments are performed to investigate the combustion control and low emission enabling without sacrificing the high compression ratio (18.2:1). The intake boost, exhaust gas recirculation (EGR) and injection pressure are independently controlled, and thus their effects on combustion and emission characteristics of the high load operation are investigated individually. The low temperature combustion is accomplished at high engine load (16~17 bar IMEP) with regulation compatible NOx and soot emissions.

The focus of this paper is the development and modelling of a reverse-poppet valve train assembly, placing a major emphasis on the optimization routine used to develop a short-duration camshaft profile. A user-programmable script, known as the penalty function, was written to assign weighted numeric values to certain parameters associated with the valve lift profile and its derivatives. These design parameters include maximum acceleration, peak lift, area under the lift curve and minimization of jerk. Optimization tools built into Matlab were then used to generate a profile which minimizes the overall ‘penalty’ associated with each parameter as it deviates from a user-defined ideal. A commercially available multi-body dynamics software package was used to evaluate the dynamic performance of the valve train incorporating the generated cam profile. A flexible-body spring element provided insight into spring surge and coil contact.

The use of gasoline fuels in compression ignition engines, with or without diesel pilots, has shown encouraging progress in engine efficiency and emissions. The dual fuel combustion of gasoline-diesel offers the flexibility of modulating the cylinder charge reactivity, but an accurate and reliable control over the ignition in the dual fuel applications is more challenging than in classical engines. In this work, the gasoline-diesel dual fuel operation is investigated on a single cylinder research engine. The effects of the intake boost, exhaust gas recirculation (EGR) rates, diesel/gasoline ratio, and diesel injection timing are studied in regard to the ignition control. The results indicate that at low load, a diesel pilot can improve the cylinder charge reactivity and reduce emissions of incomplete combustion products.

The need for green energy and less fuel consumption is a non-stop demand for researchers and academia from the industry and the automotive market. Several solutions were found and some are being practiced and commercialized. Plasma Electrolyte Oxidation (PEO) technique is a fast growing approach to resolve the weight load in automotive industry by creating a thin layer of a ceramic coating on lighter alloys such as aluminum for different parts like engine blocks. Of course in a hot and corrosive environment such as an engine, the main concern would be corrosion and wear effects on the engine. The goal of this research is to study the effect of different factors such as solution type, power input variations and coating thickness on wear resistance of aluminum Al 319.

The following paper presents an outline of the current state of driver modeling along with the various methods that are employed in their development. In recent years, vehicle manufacturers have implemented various systems that, in some manner, improve the operation of their vehicles. Many of these systems include an electronically controlled device which is capable of making decisions based on the immediate conditions affecting the vehicle. Much of the influence to develop such systems stems from the issue of safety: in emergency situations the control device is capable of making a decision quicker than the driver and thus reduces the potential for some form of collision. Another motivating factor behind these systems is to improve fuel efficiency, specifically in regard to hybrid vehicles where more than one form of propulsion is used and such devices can aid the driver to operate in a more efficient manner.