Research on Lubrication and Lubricating Oil Supply Strategy of Low-speed Diesel Engine Cylinder-Piston Ring Pack

Abstract

In view of the characteristics of Marine low speed diesel engine cylinder lubrication using external oil injection, a lubrication model for cross-head two-stroke diesel engine cylinder liner and piston ring pack was established. The orthogonal experimental design method is used to comprehensively analyze the influence of three factors, “oil injection timing”, “oil feed rate” and “oil injection hole position”, on the frictional work loss of the piston ring pack. Combined with genetic optimization algorithm and BP neural network, the optimization goal is to minimize the friction loss of piston ring pack, and further quantitative analysis of the orthogonal test results is carried out. The optimized design shows that: when the thickness of the oil film at the inlet of the cylinder liner surface is 3µm, the optimal combination is “oil injection timing (advance) + 8ms, oil feed rate 0.9g/kW. h, oil injection hole position angle 140°CA”. When the thickness of the oil film at the surface inlet is 2µm, the optimal combination is “oil injection timing (advance) + 12ms, oil feed rate 1.0g/kW. h, oil injection hole position angle 100°CA”.