Sample Problem: Cylindrical Hohlraum at OMEGA

Setting Up the Grid: Cylindrical Hohlraum

Perform the following steps to set up a cylindrical hohlraum with a laser entrance hole pointing at port P6.

• Select Target | Add Object.
• Select "Cylindrical Hohlraum" for the target component type.
• Set the object name to "Hohlraum".
• In the Position tab of the Object Parameters Dialog:
• For the Reference Coordinate System, use "Target Chamber".
• Use the default object position: r = (0,0,0). That is, put the centroid of the halfraum at target chamber center.
• Use the Port Positions Dialog to find the angles to port P6. Showing the diagnostic ports in the Target Chamber coordinate system gives (for Port P6): polar angle = 63.44 degrees and azimuthal angle = 342.00 degrees.
• Enter these angles for the polar and azimuthal orientation angles.
• In the Size/Gridding tab of the Object Parameters Dialog:
  • For radius, select variable. Press the Table button.
    • In the table dialog, press the Set X Grid button. Add points ranging from 0 to 1.4e-9 sec in 0.2e-9 sec intervals.
    • In the table dialog, press the Set Y Values button. In the Analytic expression box, type: "0.08*(1-0.2*x/1.e-9)".
    • The table should now appear as shown below:

     

    

    • Press OK in the table dialog.
  • Set the hohlraum length to 0.24 cm, and LEH radius to 0.05 cm.
  • (For all pre-configured hohlraums, surface normals face inward.)
  • Use 11 grid points along the Z-axis.
  • Set the number of azimuthal grid points to 24.
  • For the end disks, use 5 radial grid points.
• Select "OK" in the Object Parameters Dialog.