Resolutions Used in Various Jet Papers

Paper Base Grid AMR Physical Size [AU] Jet Radius [AU] Lcool [AU] Cells/AU Cells/Rj Cells/Lcool
Mine (2013) 42 x 420 7 2005 x 20054 334 3 2.68 896 8.04
De Colle (2006) 180 x 1800 0 2005 x 20054 334 3 0.09 30 0.27
Raga (2007) 16 x 64 10 1671 x 6685 134 10 9.80 1314 98.05
Tesileanu (2012) 128 x 384 6 400 x 1200 20 0.2 40.96 819.2 8.19

For Raga (2007), the numbers in the table make sense for a 10 level run. These values are the same as what is actually stated in the paper However, they said that they used 11 levels. So either their simulation was actually 10 levels, and not 11, or someone did the resolution calculations wrong, or there is some detail about their refinement that I am missing.

For Tesileanu (2012), I did not see what their time-dependent velocity was, so I am not sure how strong the internal shocks are. This would determine the cooling length. I will try looking at this more closely to see if I can figure it out from their data.


UPDATE

I changed the above table a bit. Before I was using an Lcool = 4 AU for my calculations. That is still a pretty good benchmark for most of the internal shocks. However, the strongest shock would be at 100 km/s. That is the peak jet velocity of 250 km/s running into the minimum velocity material which is at 150 km/s. I ran these parameters through my 1D code and got Lcool = 3 AU. This is the minimum cooling length that I would expect to see for the internal shocks.

This calculation was done for the hydro case. However, this should be a minimum for all cases (ie MHD with different betas), because magnetic fields would only increase Lcool.

I did the same calculation for the parameters given in Tesileanu (2012), and got Lcool = 0.2 AU. This is mainly due to the increased density. This is for their models which have njet = 104. They also have models at njet = 5 x 104, so these would have an even smaller minimum cooling length.

I also did the calculation using the Raga (2007) parameters. I got Lcool = 1.9 AU. This is because they also use a higher density than in my sims. However, the cooling length they reported and used was 10 AU. They did the calculation for a 40 km/s shock, while I did it for an 80 km/s shock…For a 40 km/s shock, astrobear gets 8.30 AU which is pretty close to their 10 AU.

So my question is this: When you have the sinusoidally dependent injection velocity, is it more appropriate to consider your strongest shocks to be equal to the amplitude of your sinusoidal function, or 2x the amplitude?

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