A method for mathematical modeling of the hydrodynamic friction of plunger pairs in terms of microgeometry

The fuel injection system strongly relies on a high pressure fuel pump which is essential for its overall performance. The fuel pump plunger is subject to high loads and irregular lubrication under dynamic loads, which leads to its premature wear. The industrial sector uses laser surface micro-texturing to reduce friction and improve anti-wear properties. Its positive effects are supported by both theoretical and experimental data. The paper presents a method for determining the hydromechanical characteristics of plunger pairs during hydrodynamic friction. The microgeometry of friction surfaces was taken into account due to the lubricating fluid cavitation effect described by the modified Reynolds equation. The proposed method can be applied to develop the software to analyze the contacting surfaces of plunger pairs and evaluate their tribological characteristics based on the microgeometry parameters of friction surfaces. The paper also studies the influence of microgeometry parameters on the quality criteria of the hydromechanical characteristics of plunger pairs. It gives the calculated examples of analyzing the contacting surfaces of plunger pairs separated by a lubricant layer. The technical specifications are assessed depending on the microgeometry parameters of the friction surface roughness.