Abstract—Our recent “Direct” simulations of liquid fuel atomization in high-pressure diesel engine injectors are presented. An adaptive volume of fluid (VOF) method based on octree meshing is used, providing savings of two orders of magnitude in computational cost. Both unperturbed and perturbed inlet conditions are used, and the results are compared to the experimental measurements of Hiroyasu & Kadota. The overall agreement between the volumetric distribution of droplet diameter in our first trial (unperturbed) and the measurements from the injector far-field is very promising. The results of the perturbed simulation however, show a substantially smaller size distribution. This is attributed to the residual effect of the perturbation on the droplet, perhaps expediting the secondary atomization process. Detailed analysis of resolution requirements, interfacial instabilities, and tracking of droplets are underway to provide a complete explanation of the physical phenomena occuring. The simulations will be extended to other ambient densities, and later to higher-speed injectors, where different, and more complex breakup mechanisms are believed to be interacting with each other. Once these mechanisms are fully understood, it will be possible to create accurate models for implementation in Large Eddy Simulations (LES).
Index Terms—Atomization, breakup, DNS, VOF
Author is with the University of British Columbia's School of Engineering (Okanagan). Kelowna, BC, V1V 1V7 (e-mail: firstname.lastname@example.org)
Cite:K. Mehravaran, "Direct Simulations of Primary Atomization in Moderate-Speed Diesel Fuel Injection," International Journal of Materials, Mechanics and Manufacturing vol. 1, no. 2, pp. 207-209, 2013.