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The search for improvements in fuel economy, specific power, exhaust emissions and refinement leads to an increasing number of experimental variables and flexibility in their operating strategy. This makes identification of optimum settings and robust solutions more demanding. New test and analysis techniques are required to identify underlying trends and sensitivities in order to determine, with some confidence, the technical and commercial benefits of changes to one or more parameters. Greater emphasis on experimental design will therefore be essential for any engine research and development programme. Design of experiments (DoE) techniques have been widely used for identifying optimum settings. Traditional experimental designs can be improved by including engineering knowledge more directly into the design process and by providing information on a continuous basis during the test programme.

A stochastic model for the entire pressure-time history of cycle-by-cycle cylinder pressure variations is obtained by fitting simple parametric models of cylinder pressure development to 506 cycles of continuous experimental data taken at four operating conditions. The cyclic variation is therefore encapsulated in a sequence of cyclically varying model parameters whose statistical properties then complete the stochastic description. Different model forms, (including computationally efficient linearised models), are compared for their degree of fit, and for the ease with which the statistics of the identified parameters can be defined. This approach, which typically accounts for 80-90% of the rms cyclic pressure variation, provides a more complete quantification of the phenomena than previously available, and a basis for simulating statistically identical pressure traces.

This paper presents the conclusions of a study into the way the Formula SAE project works in the UK academic sector. The motivation for the work arose during the introduction of the project at the University of Sussex when we needed to evaluate the cost effectiveness of the project as part of the engineering curriculum. The traditional view of FSAE in the UK was that it proved a valuable recruitment tool and when only a few universities offered the project to students this was clearly the case. However now that the project is more widely adopted and where smaller Departments are now supporting the project, there is a need to look more closely at the effectiveness of the project. Identification of the factors that make a successful entry has also helped in an evaluation of the resource requirements. The general conclusion from the work is that Departments must work to extract the benefits of the project through curriculum planning.