THE PISTON DYNAMICS UNDER KNOCK SITUATION OF DIESEL DUAL FUEL ENGINE: A NUMERICAL STUDY

The compression ignition engine fueled by natural gas or Diesel Dual Fuel (DDF) engine is a promising engine for the future with a higher oil price. Unfortunately, the DDF engine knock easily: this leads to damage of a piston. So, the understanding of the piston motion in the knock situation is crucial for the safe DDF engine operation. This is the first implementation of piston dynamic study focusing on the motion of the piston of DDF engine under knock situation. The simulation model was developed recently by our research group [1]. Two sets of cylinder pressure data: original diesel mode and DDF mode under knock situation were used as input for the model. The results show that the model can contribute the understanding of tribological phenomena of the piston lubrication. A higher peak cylinder pressure slightly increases the piston lateral motion, tilt angle, side force, and impact force. Hence, the forces from piston dynamic are not the main factor of the piston damage under the knock situation