Posts by author elambrid

Meeting Update-08/05/13 - Erini

-Running a large polytrope run atm (Gmx =1283, gxbounds=-2-22222, t_final=.04d0 with timescale ~ 7.6 *106

-lineout at 2.5 sound crossing time

-pseudo

No explosion persay, but definitley some odd boundary effects. This is the longest run I have done at this resolution.

-check out u/Polytropes - for it is updated

Meeting update - Erini 7/29/13

Meeting Update 7/23/13 -Erini

  • I have been working on my ticket #303
  • I had some confusion in terms of various global.data parameters that I have cleaned through, thus the following two gifs represent my issues

n=3 res:80^3 comp cell size: 2's - notice the asymmetry n=1.5 res:80^3 comp cell size: 2's

-beginning to think that some of the issues might actually be with the numerics ​http://adsabs.harvard.edu/full/2000PASJ...52..217H

Horedt lists that the density ratio is a dependent criteria in the stability equation for embedded polytropes - perhaps the density ratio being used is too high, e-mailed prof blackman and perhaps he can provide some insight on the usefulness of the paper

Erini - Meeting Update - July 1st 2013

  • polytrope is on grid
  • Parameters:
    grid resolution: 64 cubed
    domain: -2d0 -2d0 2d0 2d0 2d0
    final times used: (.001, .01)
    frames used: (10,20)
    timescale: 7655157.60438493

→ so for the .01 final time, we have 76551.57…yikes too small
→ so for the .01 t final time and 20 frames case we get the following density pressure

Erini - Meeting Update- June 24th 2013

  • having scaling errors with polytrope profile
  • I initially got it to produce a first cut off polytropic profile (domain size too small) that agreed with literature for the well documented case of n=3
  • upon trying to fix the scaling errors - I am now getting NANS
  • still chugging away, but ever closer each day

Meeting Update June-17th Erini

  • Got the code to compile
  • It's freezing and doesn't run - trying to figure out where it's crashing!
  • So here is what I'm trying to change in terms of initializing: 
putting the profile object on the ambient object

having the ambient density and pressure be the boundary density and pressure for the polytrope... ideas?

Meeting Update June 10th - Erini

Almost done with polytrope stuff

I reformatted everything so that input params were central density, Mass and polytropic index as opposed to central density, star radius and polytropic index…but i have now run into an issue

Trying to figure out a way to approximate cell length - I was previously difining it as: cell length = R_outer/npoints

Code finds R_outer AFTER the integration, any ideas as to how to find a good bound for cell length without radius being an input?

Erini's Update -4/23/13

  • still working on polytrope module
  • almost done writing up generalized polytropes for wiki

Erini's Update 4/16/2013

  • finished LE_module
  • made a project page for it

Erini's Update 4/1/13

  • i have made a test polytrope code, it is located in my test directory if anyone is interested

-i have tried to upload a couple of images, but embarrassingly enough I cannot get it to work on the wiki

  • my dimensionless total radius matches to at least 4 decimal places to Chandrasekhar's table and current tables

Erini's Update 3/25-2012

-met with Erica, and Professor Blackman, and Jonathon

  • coding numerically the lane-emden equation as opposed to the approximate analytic paper I initially started with
  • Jonathon led me through using various read-in profiles, which I will ultimately need to do with lane emden module
    • option of using stellar evolution code data from public tables

Erini's Update -3/18/13

Began coding the analytic approximate solution for the general case of the Lane Emden equation, I am using the solution derived here:​F.K.Liu's Polytropic Gas Spheres: An Analytic Solution to the Lane Emden Equation(this is the same paper Erica used for her isothermal case, n= \(\infty\)).