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A computational investigation of engine flow in an optical water analog engine has been carried out using KIVA. Three cases (20 RPM, 40 RPM and 60 RPM) are examined and discussed. From the comparison of the three different cases, there are obvious cyclic variations for different piston velocities. The discrepancies in the cases demonstrate that the transition to turbulence occurs at the lower RPM (e.g. 20 RPM) while fully developed turbulence seems to start at the higher RPMs (e.g. 40 and 60 RPM). These, therefore, suggest that 2D PIV used in previous measurement is valid at lower RPM because the measurement actually measures the jet or the turbulence transition from jet, but 3D stereoscopic PIV is certainly better and necessary at higher RPM due to the 3D character of the turbulence. The work will assist in the design of new experiments, and provide direction for improving modelling techniques.

In this, Part 1 of the paper, the sound generation of a diesel engine is modelled based upon the combustion process, and time-frequency analysis is used to reveal the underlying characteristics of the sound waves. Simulation shows that the frequency bandwidth of the generated acoustic signals is significantly widened around the engine's top dead centre (TDC) positions, with the energy concentrated predominantly at the firing frequency and its harmonics. As anticipated, the model predicts an increase in sound level with increasing engine load and speed, and the model-predicted noise generation is correlated with waveforms extracted from intrusively-monitored cylinder pressure. Real monitored data, taken in an ordinary engine test-bay environment and without special acoustic monitoring precautions, is shown to be highly contaminated due to adverse environmental acoustics and intrusive background noise.

In this paper, the focus is upon the condition monitoring implications of acoustic monitoring. Namely, its ability to detect, diagnose and locate incipient deterioration in a number of common failure modes. To improve the reliability of the condition monitoring procedures, the noise contaminated signals are conditioned based upon the results of speed and load dependency investigation of the identified low and high frequency regions of sound. High pass filtering is shown to eliminate much of the environmental dependency of the monitored signals, whilst retaining the pertinent condition indicating information content. Real fault testing shows that the location of different faults, their influences upon combustion, and the ability to distinguish between them can all be extracted from the shape of the contours in the Continuous Wavelet Transform (CWT).

This paper presents results and analysis of experiments carried out on a vehicle platoon control system developed in the PATH program. The objective of this project is to assess the feasibility of applying currently available technology to the concept of vehicle platoon control. It is estimated that the vehicle platoon system could increase highway traffic capacity by a factor of two or three. The Integrated Platoon Control System (IPCS) includes a control system, communication system, data acquisition system, and various sensors including a radar system. The initial experiments using two Ford cars showed successful results. In the field tests, the automated following vehicle successfully followed the manually driven lead vehicle through several different kinds of maneuvers. This project is a joint effort by U.C.Berkeley, Caltrans and VORAD, with vehicles provided by Ford.