Vortex shedding is an oscillating flow that is commonly observed in fluids due to the presence of a blunt body in a flowing medium .
Numerical simulations have shown that the phenomenon of vortex shedding could also develop in the magnetohydrodynamic ( MHD ) domain .
The dimensionless Strouhal number , the ratio of the blunt body diameter to the product of the period of vortex shedding and the speed of a flowing medium , is a robust indicator for vortex shedding , and , generally of the order of 0.2 for a wide range of Reynolds number .
Using an observation from the Atmospheric Imaging Assembly on board the Solar Dynamics Observatory , we report a wavelike or oscillating plasma flow propagating upward against the Sun ’ s gravitational force .
A newly formed shrinking loop in the post-flare region possibly generates the oscillation of the upflow in the wake of the hot and dense loop through vortex shedding .
The computed Strouhal number is consistent with the prediction from previous MHD simulations .
Our observation suggests the possibility of vortex shedding in the solar corona .