Micro-manufacturing : research, technology outcomes and development issues

Besides continuing effort in developing MEMS-based manufacturing techniques, latest effort in Micro-manufacturing is also in Non-MEMS-based manufacturing. Research and technological development (RTD) in this field is encouraged by the increased demand on micro-components as well as promised development in the scaling down of the traditional macro-manufacturing processes for micro-length-scale manufacturing. This paper highlights some EU funded research activities in micro/nano-manufacturing, and gives examples of the latest development in micro-manufacturing methods/techniques, process chains, hybrid-processes, manufacturing equipment and supporting technologies/device, etc., which is followed by a summary of the achievements of the EU MASMICRO project. Finally, concluding remarks are given, which raise several issues concerning further development in micro-manufacturing

An experimental study of gasoline effects on injection rate, momentum flux and spray characteristics using a common rail diesel injection system

A comparative study using diesel fuel and gasoline has been conducted focusing on the injection process. In this paper an experimental study has been carried out comparing the effects of the different fuels on the mass flow rate, momentum flux and spray visualization in non-reactive conditions with a conventional common rail system with a multi-hole injector and two different nozzle designs. Analysis of the results for both fuels show no significant variations of the momentum flux between fuels while mass flow appears to be higher for diesel with respect to gasoline when the injector needle is fully open. The use of gasoline in these injectors seems relevant in the opening and closing phases of the injector. The high-speed imaging under non-evaporative conditions revealed that both diesel and gasoline spray penetration are "quite" similar and the statistical analysis of the results shows good agreement with the literature, furthermore new parametric correlation for gasoline is presented in this work. No major differences in the spray cone angle have been found either, showing consistency with the momentum flux measurements.The authors wish to acknowledge General Motors for supporting this research.Payri, R.; García Martínez, A.; Doménech Llopis, V.; Durrett, R.; Plazas, AH. (2012). An experimental study of gasoline effects on injection rate, momentum flux and spray characteristics using a common rail diesel injection system. Fuel. 97:390-399. doi:10.1016/j.fuel.2011.11.0653903999