Applying Different Strategies within OpenFOAM to Investigate the Effects of Breakup and Collision Model on the Spray and inCylinder Gas Mixture Attribute

In the current study, a 3D numerical simulation of twophase flow has been conducted in a direct injection CI engine using the EularianLagrangian approach and a new breakup model. The newly modified breakup scheme has been implemented for simulating the ultrahigh pressure diesel injection. The effects of droplet breakup and collision model on the spray and incylinder gas characteristics have been examined using the open source code OpenFOAM. Spray penetration and cone angle are investigated as spray properties and surrounding gas motion are studied by incylinder gas velocity and pressure distribution for nonevaporating conditions. In addition, vapor penetration of the evaporating spray is presented to study the effects of current scheme on the evaporating condition. The continuous field is described by RANS equations and dynamics of the dispersed droplet is modeled by Lagrangian tracking scheme. Results of the proposed modified KHRT model are compared against other default methods in OpenFOAM and favorable agreement is achieved. Robustness and accuracy of different breakup schemes and collision models are also verified using the published experimental data. It is demonstrated that the proposed breakup scheme and Nordin collision model display very accurate results in the case of ultrahigh pressure injection.