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 ** COPYRIGHT (C) 1996-2013, XYZ Scientific Applications, Inc.                 **
 **                                                                       **
 ** These coded instructions, statements, and computer programs  contain  **
 ** unpublished  proprietary information of XYZ Scientific Applications,  **
 ** Inc., and are protected by Federal copyright law.  They  may  not be  **
 ** disclosed  to  third  parties  without  the prior written consent of  **
 ** XYZ Scientific Applications, Inc.                                     **
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ABOUT THIS TEMPLATE

                  INPUT FILE: input
       TEMPLATE FILE TO EDIT: template

The geometry for the nacelle under consideration is assumed to
be oriented in a standard way, and all surfaces for the spinner
grouped into 1 TrueGrid composite surface.  Similarly, all
surfaces for the nacelle should be grouped into 1 TrueGrid
composite surface.

After the geometry is oriented and grouped, a few parameters
must be set to reflect gross bounds and element sizes for the
mesh.  Everything else is automatic.  It will take some time
for the problem to run because of elliptic smoothing commands.
(It takes about an hour on an HP 9000/712.)


1. ORIENT THE GEOMETRY

   (*) Import the IGES file for this problem using

             iges IGES-file-name 1 1;

   where IGES-file-name is the name of your IGES file.

   (*) Use the Environment Window labels options to label points
   on surfaces.  Zoom way in on the tip of the spinner, and select
   the point at the tip.  Save the coordinates by typing a 'C'
   in the text window, followed by a space.  Then press F9 to
   print the coordinates of the labeled point, and hit RETURN.

           C 1.4171407e+02 8.4668256e-02 -2.6270186e-10

   Change the parameters 'xcenter', 'ycenter', 'zcenter' to the
   coordinates of this point (lines 30-32 of the template file).

           line 29:  para
                        xcenter  1.4171407e+02
                        ycenter  8.4668256e-02
                        zcenter -2.6270186e-10
                     ;


   (*) Determine a rotational transformation to position the
   geometry so that
        (i) The positive z-axis coincides with the axis of the
            spinner, and points in the same direction as the spinner;
       (ii) All cylindrical angles of the geometry are between
            0 and 180 degrees.
   Replace the transformation on line 36 of the input file with
   your transformation.

           line 36:    ry 90

   Be sure to change the name of the IGES file.

           line 34:    iges /users/d/BOEING1/nnacell.igs 1 1
                            ^^^^^^^^^^^^^^^^^^^^^^^^^^^^

2. GROUP THE GEOMETRY

   Label the surfaces using an appropriate labels option in the
   Environment window.

   Replace the numerical range 1:14 on line 41 with the surface
   numbers of all surfaces of the nacelle (outer ring)

                line 41: sd 101 sds 1:14;

   Replace the numerical range 15:17 on line 45 with the surface
   numbers of all surfaces of the spinner.

                line 45: sd 102 sds 15:17


3. ESTABLISH GLOBAL BOUNDS

   Specify a maximum z-coordinate for the problem.  This z-coordinate
   should be at least 20 units larger than the largest z-coordinate of
   any point of the geometry (30 or 40 is better)

               line 49:  zmax      100

   Specify a minimum z-coordinate for the problem.  A z-plane at the
   chosen value must NOT be below any part of the lower edges of the
   nacelle or spinner surfaces.

               line 50:  zmin      -80

   Specify a maximum radius.  This radius must be at least 20 units
   larger than the largest radius of any point on the geometry (30
   or 40 is better)

               line 51:  rmax      120

4. SPECIFY ELEMENT SIZES, DENSITIES

   Boundary layers are automatically constructed as "offsets" of the
   original geometry.  These layers are chosen to be about 10-12 units
   thick.  These boundary layers are fixed, except that the number of
   elements in them, as well as the size of the first layer, can be
   specified.

        NUMBER OF ELEMENTS IN BOUNDARY LAYER AROUND THE NACELLE
               line 53: naclayer   30

        THICKNESS OF THE FIRST LAYER AROUND THE NACELLE
               line 54: naclsiz    .0001

        NUMBER OF ELEMENTS IN BOUNDARY LAYER AROUND THE SPINNER
               line 55: spinlayer  18

        THICKNESS OF THE FIRST LAYER AROUND THE SPINNER
               line 56: spinlsiz   .001

   The element size in unzoned regions determines all other densities:

        APPROXIMATE SIZE OF ELEMENTS IN UNZONED REGIONS
               line 58: elemsize    3.5

   Element densities everywhere are adjusted so that elements in unzoned
   regions will be *about* elemsize by elemsize units.

5. RUN THE MODIFIED TEMPLATE

          tg i=input len=40

   After the geometry is imported and additional curves are constructed
   the program will begin an interactive session.  Make sure everything
   looks okay at this point.

The block structure for the cylindrical mesh is as shown

                 r = 0
                   _______________________________     z = zmax
                  |   |        |           |      |
                  |   |        |           |      |
                  |   |        |           |      |
                  |___|________|___________|______|
                  |   |        |\         /|      |
                  |   |        | \ _____ / |      |
                  |   |        |  |     |  |      |
                  |   |        |  |     |  |      |
                  |___|________|__|     |  |      |
                   \   \       |  |     |  |      |
                   |   |       |  |     |  |      |
  Z                |   |       |  |     |  |      |
 / \               |   |       |  |     |  |      |
  |                |   |       |  |     |  |      |
  |                |   |       |  |     |  |      |
  |     \          |   |       |  |     |  |      |
   ----- R         |___|_______|__|_____|__|______|    z = zmin
        /
                    |  |       |  |            r = rmax
                    |  |     > |  | <
                    |  |    'naclayer' number of elements
                    |  |    'naclsiz'  is the size of the first layer
                    |  |
                  > |  | <
                 'spinlayer' number of elements
                 'spinlsiz'  is the size of the first layer


User Specified Parameters

         zmax        : maximum z-coordinate of mesh
         zmin        : minimum z-coordinate of mesh
         rmax        : maximum r-coordinate of mesh
         naclayer    : number of elements near the nacelle
         naclsiz     : size of the first layer near the nacelle
         spinlayer   : number of elements near the spinner
         spinlsiz    : size of the first layer near the spinner
         elemsize    : rough size of elements in unzoned regions

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Copyright © 1996-2013 XYZ Scientific Applications, Inc. All rights reserved.