Temperature–friction characteristics of used lubricant from two-stroke cross-head marine diesel engines

It is now quite apparent that, in a two-stroke, cross-head marine diesel engine, the lubrication regime in the contact between piston ring and cylinder liner at the top dead centre (TDC) is of a boundary type. Therefore, the tribological performance of a system to simulate the real contact should be assessed under conditions closely resembling the operating engine environment. In the reality of engine operation, the lubricant is often contaminated by fuel and products of combustion, hence the need to study the temperature–friction characteristics of this actual lubricant under the conditions of boundary lubrication.