Tornadoes are known to sometimes consist of a main vortex and several satellite vortices. It is suspected that much of the wind variability and extreme damage from tornadoes may be attributable to these satellite vortices. In this research, the Principal Investigator will utilize a well tested direct numerical simulation to study satellite vortices. The purpose of the research is to understand the characteristics of the satellite vortices and especially to investigate the ratio of the wind speed in the satellite vortex to the wind speed in the larger vortex. The physics controlling the larger vortex are somewhat well known and are more amenable for simulation in a complete thunderstorm model. This research will focus on a systematic, high-resolution investigation of the lower part of a tornado vortex, which would be difficult to do with a thunderstorm model.
The broader impacts are as follows. First, societal issues and risk management for tornadoes will be improved with knowledge of the frequency and distribution of wind speeds in satellite vortices. Second, a limiting factor in satellite vortex intensity is the spiral vortex breakdown, a phenomenon of interest to fluid engineering. The engineering interest in vortex breakdown will be impacted by the simulations and analysis.
