Two-phase film dynamics on diesel injector nozzles
: deposition, phase transition and removal processes

  • Dan Sykes

    Student thesis: Doctoral Thesis


    Enhancement of combustion and air-fuel mixing processes plays a principal role in meeting regulated emissions targets. Unburnt hydrocarbon emissions are reduced through elevated gas temperature and pressures with smaller internal cavities in injector nozzles, refining fuel-air mixing and combustion performance. Despite the clear benefits, the modifications elicit conditions conducive of fuel degradation and deposit forming reactions in surface-bound fuel films, reducing injector durability. The reduction of NOx and soot has been addressed through the adoption of multiple injection strategies, effectively resolving the NOx, soot and piston work trade-offs whilst lowering engine noise. However, the technology gives rise to a higher frequency of transient injection phases, presenting a persistent source of surface-bound fuel and unburnt hydrocarbons emissions.
    Date of AwardSept 2021
    Original languageEnglish
    Awarding Institution
    • University of Brighton
    SupervisorCyril Crua (Supervisor), Guillaume De Sercey (Supervisor) & Sergei Sazhin (Supervisor)


    • High-speed microscopy
    • dribble
    • idling
    • valve covered orifice
    • split injections
    • cavitation
    • orifice bubble
    • transient phases
    • rarefaction
    • phenomenological model
    • end of injection
    • fuel discharge
    • gas ingestion
    • surface films
    • low load
    • nearnozzle region
    • injector deposit
    • spray wetting

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