omega_rod = 0	2	5	10	15

Figure1. Shows contours that as a full rod is rotated at increasing rates the vortex bubble is eliminated. However note that a new bubble at the top (near the lid) appears.
 
 

omega_rod=0	5	10	15	25

Figure 2. Shows that a co-rotating rod at the top (near lid) reduces the bubble size much as with a full rod. Although at high rotation rates the bubble persists. Note as in the full-rod case the appearance of the top bubble.
 
 

(a)	(b)	(c)	(d)
omega_rod=0	2	5	20

Figure 3. Shows that a co-rotating rod at the bottom, with extent close to that of the bubble increases the bubble size as the rotation rate is increased. Note the presence of the short rod modifies the bubble shape and size of the bubble from the no-rod and the full-rod cases.
 
 

omega=0	-5 (unsteady)	-20 (unsteady)

Figure 4. Shows that a counter-rotating rod at the bottom, fails to supress the bubble and causes unsteadiness as the rotation rate is increased.