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The paper presents a novel method for the measurement of lubricant film thickness in the piston-liner contact. Direct measurement of the film in this conjunction has always posed a problem, particularly under fired conditions. The principle is based on capturing and analysing the reflection of an ultrasonic pulse at the oil film. The proportion of the wave amplitude reflected can be related to the thickness of the oil film. A single cylinder 4-stroke engine on a dyno test platform was used for evaluation of the method. A piezo-electric transducer was bonded to the outside of the cylinder liner and used to emit high frequency short duration ultrasonic pulses. These pulses were used to determine the oil film thickness as the piston skirt passed over the sensor location. Oil films in the range 2 to 21 μm were recorded varying with engine speeds. The results have been shown to be in agreement with detailed numerical predictions.

Wear problems will continue to occur with engine components even with changing design and the introduction of novel materials. Very few wear models for engine components exist, however, so it is difficult for engineers to easily establish how materials and components will perform and costly engine testing programs have to be carried out. Those models that do exist are often complex, difficult to use and written in software that is not available within many organisations. The use of browser-enabled software applications is becoming increasingly common in large, multi-location organisations to make the delivery and support of engineering tools more efficient, so it would be beneficial if wear modelling software was available in this format. In this project, work has been carried out to further the development of an existing valve recession model to provide an easy to use variant for use in industry.

A study has been carried out to investigate the influence of soot contaminated automotive lubricants in the wear process of engine valve train contacts. Previous research on this topic has been performed from a purely generic and theoretical point of view. Testing has been carried out using standard testing techniques with very little relevance to real engine conditions or components. In this study the conditions under which wear occurs was investigated using tests with actual valve train components. The objective of the work was to develop a knowledge base of wear data for a variety of lubricated reciprocating valve train components. This will increase the understanding of the wear mechanisms that occur within a contaminated contact zone, which will be used in the future development of a predictive valve train wear model.