$-------------------------------------------------------------------------------
$                   RIGID FORMAT NO. 2, Inertia Relief Analysis
$        Windmill Panel Sections for Automated Multi-stage Substructuring,
$                                 Run 1, (2-2-1)
$        Windmill Panel Sections for Automated Multi-stage Substructuring,
$                                 Run 2, (2-2-2)
$        Windmill Panel Sections for Automated Multi-stage Substructuring,
$                                 Run 3, (2-2-3)
$        Windmill Panel Sections for Automated Multi-stage Substructuring,
$                                 Run 4, (2-2-4)
$        Windmill Panel Sections for Automated Multi-stage Substructuring,
$                                 Run 5, (2-2-5)
$        Windmill Panel Sections for Automated Multi-stage Substructuring,
$                                 Run 6, (2-2-6)
$        Windmill Panel Sections for Automated Multi-stage Substructuring,
$                                 Run 7, (2-2-7)
$ 
$ A. Description
$ 
$ This problem illustrates the fully automated multi-stage substructuring 
$ capability of NASTRAN. 
$ 
$ Of the total of seven runs involved, three Phase 1 runs are made, one for each 
$ basic substructure, using Rigid Format 2 in order to generate mass matrices. 
$ The combination and reduction to the final model is accomplished in seven 
$ distinct Phase 2 steps, plus eight equivalence operations. A static solution, 
$ Rigid Format 1, is obtained for each of the three load cases specified. Run 4 
$ produces actual plot output. Runs 5 and 6 demonstrate the Phase 3 data 
$ recovery for two of the basic substructures. 
$ 
$ A seventh run is made to extract normal modes using Rigid Format 3 for the 
$ reduced structure. 
$ 
$ B. Input
$ 
$ 1. Parameters:
$ 
$      r   = 50.0 in       (outer radius)
$       o
$ 
$      r   = 10.0 in       (inner radius)
$       i
$ 
$      t   =  0.1 in       (plate thickness)
$ 
$                    6
$      E   =  10 x 10  psi (modulus of elasticity)
$   
$      v   =   0.25        (Poisson's ratio)
$ 
$ 2. Boundary Conditions:
$ 
$      All points u  = theta  = theta  = theta  = 0 (permanent constraint)
$                  z        x        y        z
$ 
$      u  = 0 at HUB grid points 13, 19, 37, 43
$       x
$ 
$      u  = 0 at HUB grid points 1, 7, 25, 31
$       y
$ 
$ 3. Loads:
$ 
$      First Subcase:  centrifugal force due to unit angular velocity
$ 
$      Second Subcase: unsymmetric load - right panel in tension, bottom panel 
$                      in compression, F = 100 uniformly distributed over each 
$                      loaded edge 
$ 
$      Third Subcase:  F = 1.0 applied at HUB grid point 4 inward radially
$ 
$ 4. Substructuring Parameters:
$ 
$      SOF(1) SOF0,950 $ CDC
$ 
$      SOF(1) = FT18,950 $ IBM
$ 
$      SOF(1) = INPT,950 $ UNIVAC
$ 
$      PASSWORD = DEMO
$ 
$      OPTIONS = K, M, P
$ 
$ C. Theory
$ 
$ This problem is designed to illustrate the use of automated multi-stage 
$ substructuring. No closed form solution is available. Results are compared 
$ with non-substructured NASTRAN solutions. 
$ 
$ D. Results
$ 
$ The solutions of the final reduced structure using both Rigid Format 1 and 
$ Rigid Format 3 are in excellent agreement with the non-substructured 
$ solutions. Displacements at selected points and eigenvalues are compared in 
$ Table 1. The values presented were obtained from executions on IBM equlpnent. 
$ Values obtained from CDC and UNIVAC are of the same order of magnitude with 
$ slight differences attributable to round-off of very snall numbers. 
$ 
$             Table 1. Comparison of Displacements at Selected Points
$                           for Windmill Panel Problem
$ -----------------------------------------------------------------------------
$                          Subcase 1                     Subcase 2
$ -----------------------------------------------------------------------------
$ Name/Point/Comp  Single Step    Substructure   Single Step    Substructure
$ -----------------------------------------------------------------------------
$ VANE1/1/X        -5.6x10^-14    -5.2x10^-14    -2.19155x10^-5 -2.19155x10^-5
$ 
$ VANE1/1/Y        -6.88493x10^-7 -6.88488x10^-7 8.6081x10^-1   8.6081x10^-1
$ 
$ RVANE1/1/X       4.4x10^-14     2.1x10^-13     2.19155x10^-5  2.19155x10^-5
$ 
$ RVANE1/1/Y       -6.88493x10^-7 -6.88488x10^-7 3.85998x10^-4  -3.85997x10^-4
$ 
$ HUB/5/X          -3.5x10^-14    -4.8x10^-14    1.04757x10^-5  1.04757x10^-5
$ 
$ HUB/5/Y          6.70493x10^-8  6.70488x10^-8  -6.43969x10^-7 -6.4397x10^-7
$ ------------------------------------------------------------------------------
$ Frequency, cps       -               -               -              -
$ ------------------------------------------------------------------------------
$ 
$ ----------------------------------------------
$                       Eigenvector #1          
$ ----------------------------------------------
$ Name/Point/Comp  Single Step    Substructure  
$ ----------------------------------------------
$ VANE1/1/X        1.000000       -.999752
$                                               
$ VANE1/1/Y        -8.612x10^-9   3.297x10^-7
$                                               
$ RVANE1/1/X       1.000000       -.999748
$                                               
$ RVANE1/1/Y       1.264x10^-9    -1.688x10^-7
$                                               
$ HUB/5/X          -1.46899x10^-1 1.46636x10^-1
$                                               
$ HUB/5/Y          -3.140x10^-9   -7.8304x10^-6
$ ----------------------------------------------
$ Frequency, cps   288.3          288.3
$ ----------------------------------------------
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