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spin:esc202_fs2020 [2020/03/30 14:18]
stadel [List of assignments]
spin:esc202_fs2020 [2020/05/04 08:12] (current)
stadel [List of assignments]
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 30. Mar. 2020: {{ :​spin:​sins2-05.pdf |SPH Continued}} (Videos sph3.mp4 and sph4.mp4 **see above link**) 30. Mar. 2020: {{ :​spin:​sins2-05.pdf |SPH Continued}} (Videos sph3.mp4 and sph4.mp4 **see above link**)
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 +6. Apr. 2020: {{ :​spin:​sins2-06.pdf |SPH Continued}} (Video sph5.mp4 ​ **see above link**)
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 +20. Apr. 2020: {{ :​spin:​sins2-07.pdf |2-d Ising Model}} (Video ising.mp4 ​ **see above link**)
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 +27. Apr. 2020: {{ :​spin:​sins2-08.pdf |2-d Traveling salesman problem}} (Video tsp.mp4 ​ **see above link**)
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 +3. May 2020: **Start of group projects!**
 ====== Assignments ====== ====== Assignments ======
  
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 {{ :​spin:​esc202-planetesimals.zip | esc202-planetesimals data file}} {{ :​spin:​esc202-planetesimals.zip | esc202-planetesimals data file}}
  
-3. **SPH Density calculation using Kernel**: You can use the data set from your planetesimals simulations to calculate the densities and make nice color density plots of the planetesimal disk. As discussed in the Zoom meeting: you should try to put uniform randomly distributed particles in a box from [0,1)x[0,1) (2-D) and calculate the density. You should see a bias that the density is too low at the edges. If you do this with a correctly working working periodic boundary condition density code you should no longer see this bias. Please think about how to efficiently calculate the density using nearest neighbors with periodic boundary conditions. Even better, implement it in your code and test it!+3. **SPH Density calculation using Kernel**: You can use the data set from your planetesimals simulations to calculate the densities and make nice color density plots of the planetesimal disk. **As discussed in the Zoom meeting:** you should try to put uniform randomly distributed particles in a box from [0,1)x[0,1) (2-D) and calculate the density. You should see a bias that the density is too low at the edges. If you do this with a correctly working working periodic boundary condition density code you should no longer see this bias. Please think about how to efficiently calculate the density using nearest neighbors with periodic boundary conditions. Even better, implement it in your code and test it! 
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 +4. **Sedov Taylor Explosion in SPH**: Set up a uniform grid of SPH particles in a 2-D unit cell. Make it so that there are an odd number of particle on a side, such that you have a particle centered exactly in the center of the unit cell. All particle should have v = 0 and mass = 1/N, where N is the total number of particles such that the mass of the fluid in the unit cell is 1. If we use gamma=2, then for e=1 we have c=sqrt(2) for all particles and the SPH code should maintain the uniform density as everything should be in pressure equilibrium. Test this. Now set the specific internal energy of the central particle to e = 100! Now the gas should react by producing the Sedov-Taylor blast wave. You will have to think about the appropriate timestep for the simulation. Think back to the Courant Condition from the first semester, or simply experiment with different values (hint: you know the sound speed, but what is the grid speed? What defines a resolution length scale here? h? So could we regard h/delta_t as a "grid speed"?​ 
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 +5. **2-d Ising Model** 
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 +6. **2-d Travelling Salesman Problem**
  
-4. **Sedov Taylor Explosion in SPH**: details to follow... 
spin/esc202_fs2020.1585570719.txt.gz · Last modified: 2020/03/30 14:18 by stadel