Aerospace Research and Development Directorate, Japan Aerospace Exploration Agency (JAXA)
Aerospace Research and Development Directorate, Japan Aerospace Exploration Agency (JAXA)
Aerospace Research and Development Directorate, Japan Aerospace Exploration Agency (JAXA)
Aerospace Research and Development Directorate, Japan Aerospace Exploration Agency (JAXA)
Graduate School of Engineering, Nagoya University
18 June-19 June, 2009, Japan Aerospace Exploration Agency
抄録(英)
Large-scale numerical simulations of liquid fuel jet have been conducted to elucidate the physical mechanism of primary atomization near the injection nozzle. The grid resolution is made fine enough to resolve the smallest physical scale that is determined by the Weber number, i.e. surface tension effect. Such calculations have not been performed before, and this paper reports the world's first results on primary atomization in a turbulent spray. Physical processes are well captured such as surface instability development, ligament formation and droplet generation. While the aerodynamic force plays a role in developing surface instability, surface tension becomes more dominant in ligament and droplet formation. The droplet pinch-off is mostly dominated by the short-wave pinch-off mode, as the ligaments have tips. This is consistent with our previous research on droplet pinch-off from slow laminar liquid jets and provides insights into modeling. By these results, our understanding is made deeper on what is actually occurring inside a turbulent spray. The computational performance of JAXA's new supercomputer JSS is also described. Combined with the VisIMPACT parallelization method, this kind of large-scale computation can be easily implemented. With the reduction in I/O time, large unsteady simulations like this have been becoming possible.
内容記述
形態: カラー図版あり
内容記述(英)
Physical characteristics: Original contains color illustrations