Classification of Impingement Behavior of Spray Droplets on Lubricating Oil Film in Diesel Engine by Dimensionless Number

Abstract

The purpose is to construct a model to predict the impingement behavior of diesel spray on lubricating oil film in postinjection. In this report, the impingement behavior of different liquids simulating spray droplets and lubricating oil is measured, and the critical K-factor is calculated to classify the droplet splashing and deposition behavior considering the difference of dynamic viscosity coefficient and the impingement angle of droplets. The critical K-factor was calculated from the experimental results as follows. K_cr=(We_d・La_d^0.2・(2θ/π)^-2.06)_cr=2100+6270δ_non^1.44・κ^1.10, We_d is Weber number, Lad is Laplace number, θ is impingement angle, κ is dynamic viscosity ratio.