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Increasingly stringent emission standards have promoted the interest in alternate fuel sources. Because of the comparable energy density to the existing fossil fuels and renewable production, alcohol fuels may be a suitable replacement, or an additive to the gasoline/diesel fuels to meet the future emission standards with minimal modification to current engine geometry. In this research, the combustion characteristics of neat n-butanol are analyzed under spark ignition operation using a single cylinder SI engine. The fuel is injected into the intake manifold using a port-fuel injector. Two modes of charge dilution were used in this investigation to test the limits of stable engine operation, namely lean burn using excess fresh air and exhaust gas recirculation (EGR). The in-cylinder pressure measurement and subsequently, heat release analysis are used to investigate the combustion characteristics of the fuel under low load SI engine operation.

The effects of engine noise in plastic manifolds has been a subject of study in the automotive Industry. Several SAE papers have been published on the subject. Most testing described requires access to engine dynamometers and other elaborate equipment. As part of a general study of plastic intake manifold noise characteristics, this study was undertaken to develop a synthesis bench for enabling low cost noise testing of plastic induction systems including plastic manifolds. Computer simulation of engine intake noise was used as part of a correlation between the plastic manifold synthesis bench and actual engine measurements. The Fast Fourier Transform (FFT) analysis provided analogous results between the predicted theoretical and two measured signals with a fundamental frequency at approximately 80 Hz. Qualitative and statistical comparisons of the time domain signals also proved equally favourable. Recommendations are included for further development of this approach.

Proper design of an engine's intake and exhaust system can offer the benefits of torque increase, fuel economy, and emission control. A new concept of intake airflow dynamics is presented, with a multiport model of an intake tube. Fluid transmission line dynamics are applied to a distributed parameter model of straight-tube manifold. This application proved itself to be an excellent way of analyzing the intake system predicting intake pressure waves of an internal combustion engine. With this modeling, transient and frequency responses are obtained to setup a design basis for the intake manifold.

Due to considerable efforts of automobile manufacturers to attenuate various noise sources within the passenger compartment, other sources, including induction noise have become more noticeable. The present study investigates the feasibility of using a non-conventional noise cancellation technique to improve the acoustic performance of an automotive induction system by using acoustic energy derived from the exhaust manifold as the dynamic noise source to cancel intake noise. The validity of this technique was first investigated analytically using a computational engine simulation software program. Using these results, a physical model of the bridge was installed and tested on a motored engine. The realized attenuation of the intake noise was evaluated using conventional FFT analysis techniques as well as psychoacoustic metrics including loudness, sharpness, roughness and fluctuation strength.

The Automotive market for designing and manufacturing of plastic intake manifolds in 1994 was kick started by the first large scale lost core part in N. America, the Dodge Neon. Because of the launch timeframe and the novelty of the technology in N. America this was based upon a lost core cell installed in the Siemens Windsor plant, and built as a “turn key” operation from a European injection molding machine supplier. Deliveries from that cell were over 200,000 parts by the end of 1994. Further developments of the plastic manifolds have resulted in growth to a projected annual of 2,000,000 deliveries in 2001 from the same “home base” plant. This spectacular growth has fueled a rapid development of design and manufacturing processes, cell design, in lost core with parallel developments in shell designs and processing. This paper discusses the growth of the lost core design / development activities and references some of the shell parallels.

Current plastic intake manifolds are manufactured using the injection molding process. In this paper, thermoforming is explored as an alternative to injection molding for making intake manifold shells, which can then be joined by one of the welding techniques used for thermoplastic materials. The investigation reported here includes press-forming experiments of a simple bowl shaped shell and subsequent welding experiments to join these shells.