Effects of Bubble-Wall Distance on Shock Wave Interaction with a Diesel Fuel Droplet under Conditions Related to Dual Fuel Internal Combustion Engines

In this investigation we study shock interaction of a diesel fuel droplet with diameter D in a mixed gas ambient in the vicinity to a wall (initial droplet distance H varies between H=0.5D to H=25D). The conditions are similar to single fuel (SF) ECN Spray A chamber conditions and related to dual fuel internal combustion engines (DFICE). We apply a fully conservative multi-component numerical algorithm with interface sharpening combined with “Stiffened-Gas” EOS and compute the diesel-droplet fragmentation process due to shock- droplet interaction. Our approach has been validated against reference data and shows excellent agreement. While processes like primary shock impingement, droplet deformation and droplet break-up are widely discussed in the literature, our focus is to include the effects of a reflected secondary shock (re-shock) due to the vicinity of a solid wall below the droplet. The re-shock reduces the mixture gas velocity in the main flow direction while it amplifies Richtmyer-Meshkov instibility (RMI). Depending on the initial distance between droplet and wall, various intermediate situations (PCS-situation, PSU-situation, PSC- situation) for droplet fragmentation are generated and discussed, which adds knowledge in spray and combustion processes in the DFICE environment.     «

In this investigation we study shock interaction of a diesel fuel droplet with diameter D in a mixed gas ambient in the vicinity to a wall (initial droplet distance H varies between H=0.5D to H=25D). The conditions are similar to single fuel (SF) ECN Spray A chamber conditions and related to dual fuel internal combustion engines (DFICE). We apply a fully conservative multi-component numerical algorithm with interface sharpening combined with “Stiffened-Gas” EOS and compute the diesel-droplet fr...     »