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Interest in the use of kerosene fuel in diesel engines has garnered researchers’ attention in the past few years due to its improve premixed combustion and its ability to decrease soot emission. The potential of using kerosene in the design stage of a diesel engine is thus a great motivator to study fuel spray development and to evaluate known fuel spray tip correlations and models with respect to their predictive capability with such a fuel. Therefore, the present paper proposes to investigate the spray development of a multi-hole solenoid injector fueled with kerosene under non-evaporative conditions. Moreover, the experimental results are used to evaluate how different phenomenological models proposed in the literature for diesel fuel are able to predict kerosene spray tip penetration. The experimental test rig is composed of a constant-volume pressurized vessel and a camera allowing to visualize the liquid phase using a backlight illumination technique.

The transient characteristics of the internal flow dominate all the ensuing processes: spray, fuel-air mixture formation as well as combustion and pollutants formation. Therefore, it is crucial to understand the dynamics of the injectors' internal flow. The objective of this work is to study all transient effects that may impact the internal flow of a single hole injector under different conditions. Since the numerical investigation of such a complex flow is hampered by several factors for the real operating conditions-namely the turbulence, the cavitation and the needle motion-this work is divided into two parts. In the first part, only the effects of turbulence and cavitation are considered through the study of the effects of the fuel properties as well as the injection conditions at the fully open needle position. The impact of these effects is studied by means of the Reynolds and the cavitation number.

In this paper, a semi-empiric fuel spray tip penetration model is proposed. It is applied to single and double injection strategies taking into account the early and far field penetration. The model is based on the momentum flux as initially proposed by [1] for single injection but it is derived from mean mass flow rate herein. Fuel spray interaction with entrainment air is taken into account for the second injection. The proposed model is calibrated and validated using data from 9 experiments conducted with an indirect piezoelectric diesel injector under various injection strategies. The experiments included 1) injection rate measurements using the Bosch method to determine mean mass flow rate during injector opening as well as obtaining injection duration which are both entry parameters to the model; 2) Fuel spray tip penetrations were measured in a pressure vessel using high speed photography for single and double injection strategies.

A suspension system does not merely isolate a vehicle from the shocks and vibrations induced by the road surface. It also keeps the wheels in contact with the road, ensuring vehicle stability and control. In order to properly determine the stiffness and damping parameters of a Formula SAE, models for a quarter car and a seven degree-of-freedom car (DOF-7) were developed based upon Newton's second law. These were built using MatLab/Simulink. The quarter car model was taken first, to study the effect of four (4) suspension parameters on the tires' vertical load fluctuations. The results were then used to optimize suspension parameters for the 7-DOF model, taking the bounce, roll and pitch motions of the chassis into account in addition to its four-wheel hops. Track data was acquired and used as input to the model. Nonlinear damping was implemented in the 7-DOF model to study the car's behavior.

This paper presents the effects of using E85 (15% gasoline and 85% Ethanol) on the emissions and fuel consumption of a simulated hybrid electric vehicle (HEV) as compared to the usage of gasoline fuel. The benefits of successive engine modifications to obtain a optimized E85 engine (increased compression ratio) in an HEV are quantified. The results demonstrate that the largest reduction in pollutant emissions, of between 20% and 40%, depending on the specific pollutant, is obtained when the fuel is changed to E85. Increasing the compression ratio to take advantage of the high octane rating of E85 provides a slight improvement in fuel economy and emissions. Finally, the modification of the hybrid control strategy parameters only brings about a slight improvement in fuel economy and emissions. However, the parameter values are different for the FTP and US06 cycles. This latter finding demonstrates that the hybrid strategy must be adapted to match driving conditions.