Some SURYA Output Plots

One of the subroutines that came with SURYA rescales the axes so that 1 unit on the horizontal axis takes up the same amount of physical space as 1 unit on the vertical axis (in other words: it makes a circle look like a circle) and draws some bounding semi-circles to represent a meridional slab. Some small adjustments needed to be made, as some runs were done with a proportional star of radius 0.92*R.

Another change I made was to use the dlmread command instead of the load command. This uses less RAM so larger data sets can be analyzed.

I'm not going to go into more detail about the changes I've made here.

Here are five of the plots that can be obtained with the output from a run of SURYA. This run lasted for 50 time units, which corresponds to about 150 years.

The differential rotation profile. This is calculated before the run begins. I need to look into this particular profile, as if this is rotation rate in nHz, then the equator has about a 41 day rotation period. This may have something to do with the slightly smaller star that the meridional slab was drawing.

I happen to think this plot looks better as a pcolor rather than a contour plot.

The stream function, as a contour plot and as a pcolor:

The poloidal field at the end of the run, again as a contour plot and as a pcolor. It is produced from the third column of "final.dat".

 The time evolution of the radial field at the surface:

Finally, a butterfly diagram (time evolution of the toroidal field) at the bottom of the convection zone (r = 0.7*R). It is produced from reading in "butbot.dat".

For next time, I want to see if I can pin down what's going on with the differential rotation profile, and copy enough FORTRAN to get the poloidal and toroidal diffusivity profiles to print to a .dat file. There's also a way to plot the meridional circulation without the contours of the stream function. Most importantly, I need a way to determine the period of the cycles. There's always a Fourier transform, but I'm looking into using the autocorr function instead.