Patent attributes
A method of operating a dual fuel engine includes conveying intake air, and a first fuel as a vapor and as a liquid, into a combustion cylinder in an engine, and directly injecting a second fuel into the combustion cylinder to form a first combustion charge of the first fuel as a vapor and as a liquid, the second fuel, and intake air. The second fuel is ignited to initiate combustion of the first combustion charge. Operating the dual fuel engine further includes varying at least one of, a vapor proportion of the first fuel or a total proportion of the first fuel, in a subsequent combustion charge to mitigate undesired combustion. The first fuel can include a liquid alcohol fuel. The second fuel can include a liquid compression-ignition fuel. Related apparatus and control logic is also disclosed.