Numerical simulation of primary atomization in diesel spray at low injection pressure

[EN] Atomization involves complex physical processes and gas liquid interaction. Primary atomization on diesel spray is not well understood due to the difficulties to perform experimental measurements in the near nozzle field. Hence computational fluid dynamics (CFD) has been used as a key element to understand and improve diesel spray. A recent new code for incompressible multiphase flow with adaptive octree mesh refinement has been used to perform simulations of atomization at low injection pressure conditions. The multiphase flow strategy to manage different flows is the volume of fluid (VOF) method. The adaptive mesh allows to locally refine the mesh at each time step where a better resolution is needed to capture important gradients instead of using a static mesh with a fixed and high number of cells which, in turn, would lead to an unaffordable computational cost. Even with this approach, the cell number is very high to achieve a Direct Numerical Simulation (DNS) at reasonable computational cost. To reduce the computational cost, an idea has been explored, the possibility of setting a maximum number of cells of the domain. Following this idea, the code has been tested with different configurations to understand their effects on numerical stability, the change in different spray parameters and the benefits achieved in terms of execution time. The outcomes have been validated against a theoretical model. This work was sponsored by "Ministerio de Economa y Competitividad" of the Spanish Government in the frame of the Project "Comprensin de la influencia de combustibles no convencionales en el proceso de injeccin y combustin tipo diesel", Reference TRA2012-36932 and MTM2013-41765-P. Additionally, the hardware used for the project was purchased with funding from Ministerio de economia y competitividad FEDER-ICTS-2012-06. The authors would also like to thank the computer resources, technical expertise and assistance provided by the Universitat de Valencia in the use of the supercomputer "Tirant". Salvador Rubio, FJ.; Romero Bauset, JV.; Roselló Ferragud, MD.; Jaramillo-Císcar, D. (2016). Numerical simulation of primary atomization in diesel spray at low injection pressure. Journal of Computational and Applied Mathematics. 291:94-102. https://doi.org/10.10166/j.cam.2015.03.044