Abstract
A simplified spray analysis test bench was developed to investigate the spray characteristics from a clean and a worn injector using RME and diesel fuel. A high power LED was used in this investigation to study the evolution, dispersion and transients at a frame rate of 24.4 kfps. At a constant injection pressure of 60 MPa numerous injection events have been recorded and analysed from both a new, intact injector nozzle and a nozzle which has been rejected due to wear and the presence of deposits. The resulting analysis show a worn injector will lead both to a poor injection to injection reproducibility and to the occurrence of transient effects giving a temporal strong increase of the spray width. The change of fuel type from diesel to RME occasionally leads to a delay of the occurrence of transient effects with respect to the start of injection. The poor injection to injection stability remains comparable, irrespective of the fuel used.
KEYWORDS – Fuel Sprays, RME, High speed Imaging, Injector Deposits, Worn Injector