Eliminating cavitation in diesel engines
The aim of the PREVERO project was to reduce emissions of pollutants from diesel automobile engines that impact both human health and the global climate. The approach involved redesigning fuel flow geometry with the hope of eliminating cavitation, i.e. bubble formation, thereby improving the durability of the new components. The Laboratory for fluid dynamics and thermodynamics (LFDT) of the University of Ljubljana was the PREVERO partner assigned to this task. They used a special vacuum chamber to observe the behaviour of both single bubbles and bubble conglomerations known as bubble clouds. To deal with the complex nature of the fuel flow and bubble development, the Slovenian mechanical engineers turned to a Computational fluid dynamics (CFD) model. The specific code used, named FIRE, was developed by the PREVERO coordinator, Advanced Simulation Technologies. Simulations were performed for both single and multiple bubble cases. The LFDT used FIRE to evaluate several features of cavitation, including structural function, void fraction, bubble number density, bubble clusters and bubble collapse. The resulting dataset will assist the PREVERO consortium in their efforts to redesign the fuel delivery system for diesel engines. The exercise also helped validate the suitability of FIRE for such applications.
