 |
| Magnetic field measured from one of the external magnetometers when the inner sphere is spun up to its maximum rotation rate. Semi-log plot of this growth shows a linear behavior, indicating exponential growth. |
We achieved significant magnetic activity in the redesigned system. One of the main examples of this is seen in the transient response of the field with an impulsive inner sphere start.
Exponential growth over one order of magnitude suggests dynamo growth with a time constant of 2.1 seconds. This exponential growth comes from the solution to the linear kinematic dynamo problem, for a particular eigenmode you get a set of complex eigenvalues, the real part is the growth rate. Exponential growth from the same runs in the past was insignificant and occurred over longer time scales.
This work is motivated by the successful dynamo obtained from the von Kármán Sodium experiment [1].
 |
| Bifurcation curves. (a) Measured azimuthal field growth with respect to magnetic Reynolds number (Rm). Rm is proportional to the rotational speed * radius of vessel. The solid lines correspond to a best fit with a scaling behavior (b) Measured Magnetic field Amplitude with respect to magnetic Reynolds number (Rm). |
Hi Elaine, these are some really cool figures! The past few weeks hearing you talk about the fundamentals of the experiment really helped with displaying the results. Your use of writing on the board was a great way to break down the goal of transforming the x-axis to a magnetic Reynolds number. The second figure where they were able to achieve dynamo was really interesting as well. I liked how you explained how using iron made it possible in their experiment, it helped me visualize the goal of your own work. I wanted to look at the paper it is from, but I noticed you don't have a citation for it (only [1] written in the text).
ReplyDeleteHi Elaine, I really liked the figures! After listening to your talk about the experiment, I was able to better understand the results shown on the figures. Reading through your post I noted the von Kármán Sodium experiment, however, I am unfamiliar with that experiment. I think just a brief explanation of the experiment/the outcome would allow the reader to get the gist of the paper without having to look it up. Great job!
ReplyDelete