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fevisco

• AddMat,Par2Visc
• Fluid [merge,matrix,makereduced, ...]
• Feplot
• MakeModel [Matid i]
• Range[Vect,Face,Grid,CubeEdge,rand]
• MakeSandwich layers
• StrainMap
• Test
• WriteInclude
• [Write,Build] Step12
• ceig, direct
• NASTRAN
• HandNomo FileName

 out = fevisco('command',model);

AddMat,Par2Visc

cf=fevisco('testplateLoadMV feplot');
% define material with a unit conversion
mat=m_visco('convert INSI',m_visco('database Soundcoat-DYAD609'));
%                 MatId for original, name of parameter
cf.mdl = fevisco('addmat 101',cf.mdl,'Constrained 101',mat);
fevisco('par2visc',cf);cf.Stack{'zCoef'}
cf.Stack{'info','Freq'}=[500:10:4000]';
cf.Stack{'info','Range'}=[10 20]';
fe2xf('zcoef',cf)

Fluid [merge,matrix,makereduced, ...]

• add the fluid as a superelement to the solid model
  mCP=fevisco('fluidmerge',modelS,modelF).
  
  
• assembly of the fluid/structure coupling and fluid matrices with the FluidMatrix command fevisco('FluidMatrix',cf, 'FluidInterfaceSel','SolidInterfaceSelection'). The fluid interface selection applies to the elements of the fluid superelement renumbered consistently for the combined model.
  
  The result is stored in the feplot model stack as two assembled superelements which you can access with cf.Stack{'fluid'} and cf.Stack{'FSC'}. When built with fevisco one also has coup.Node,coup.Elt with the fluid interface as fsc elements and the solid interface as quad4 elements to allow verification of the matching.
  
  Note that the coup matrix can also be imported from an external reference code that often exists in the automotive industry. fevisco('FluidMatrix',cf,coup) with coup.K, coup.sdof, coup.fdof describing the coupling matrix, solid and fluid DOFs. Solid DOFs correspond to rows of coup.K, fluid DOFs to columns.
  
  The fevisco('fluidCheckCon',cf) can be used to check the connectivity of the coupling matrix. The distance between each coupled fluid node and structural nodes involved in the coupling is computed and the associated links are shown for verification.
  
  
• compute the fluid modes and generate a reduced coupled model
  
  [mRCoup,dflu]=fevisco('fluidMakeReduced',mCP,dsol);
  
  which can then be used for predictions with fe2xf as illustrated in section 6.11.1.

Feplot

MakeModel [Matid i]

 fevisco('testplate up');cf=feplot;Up=cf.mdl;% This is a simple test case
 Up=stack_rm(Up,'mat');
 Up = fevisco('addmat 101',Up,'First area','ISD112 (1993)');
 Up = fevisco('addmat 103',Up,'Second area','ISD112 (1993)');
 MV = fevisco('makemodel matid 101 103',Up);  

Range[Vect,Face,Grid,CubeEdge,rand]

    [type cur min max vtype]

---

Figure 9.3: Positions of exact mode evaluations in parameter space. a) Hypercube face center. b) Classical 2^NP factorial plan.

---

 hcube=fevisco('RangeVect 4',[0 10])
 par=[0 0 -2 1 2;0 -1 -2 1 2;0 1 .1 2 0];
 % Uniform 3 by 4 grid on parameters 2 and 3
 hcube=fevisco('RangeGrid 3 4',par,[2 3]);hcube.val
 % Face centers on all parameters
 hcube=fevisco('RangeFace 1 2',par);hcube.val

MakeSandwich layers

 fevisco('makesandwich (layer generation)',FEnode,FEel0,treated,MAPN);

• element nature (shell or volume)
• desired material property for the meshed layer (for the starting layer use 0).
• thickness of volumes, and distances of faces to neutral fiber for shells. For shells, one has two distances from the bottom layer to the neutral axis and from the neutral axis to the top layer.

---

Figure 9.4: Example of a MakeSandwich command

---

 femesh('reset');
 femesh(';testquad4');FEel0=feutil('orient 1 n 0 0 1',FEnode,FEel0);
 femesh('divide',linspace(0,1,10),linspace(0,1,12)); 
 sandCom='makesandwich shell 0 0 .005 volume 101 .002 shell 102 -.005 .005';  
 treated='withnode{x>.5 & y>.5}'; 
 [FEnode,FEelt]=fevisco(sandCom,FEnode,FEel0,treated);
 femesh('plotelt');fecom('colordatamat');

    MAPE = feutil('get normalmap',node,elt);
    MAPN = feutil('get normalmap node',node,elt);

StrainMap

    smap = fevisco('StrainMap OffSet',model,def,SurfaceSelection)
    fevisco('StrainPlot',smap,def)

Test

WriteInclude

• the associated nodes,
• the elements selected by Selection
• the rigid links and other case information connected to the nodes used by these elements
• the material and element property information used by the selected elements

 model=fevisco('testplate');
 model=fe_case(model,'remove','Drilling');
 tname=nas2up('tempname include.dat');
 fevisco('writeinclude MatId 101 102',model,tname);

[Write,Build] Step12

ceig, direct

NASTRAN

HandNomo FileName

• Rect : define the location of the axis in the bitmap by selecting two of its corners.
• Elim : click on the text of ytick labels on the left of the axis to define the modulus range and the maximum axis value for the loss factor range.
• wlim : click on the text of ytick labels on the right of the axis to define the minimum frequency displayed on the true frequency axis (left y axis) and the min and max values for the reduced frequency (x axis).
• at : click on the isotherm that is always generated to enter the isotherm edition mode. You can then use the following keys to edit the at values. n to add new isotherm values. Left and right arrows to move the offset of the current isotherm. Up and down arrow to select a different isotherm.
  
  If the isotherm slope is not correct, check the Elim and wlim values and possibly adjust the axis rectangle using : uU to move the rectangle along -x or +x; vV to move the rectangle along -y or +y; xXyY to resize the rectangle.
  
  
• eta click on the green line with circle markers. Adjust values with your mouse. Use left and right arrows to select the points and q to exit.
• G click on the blue line with circle markers. Adjust values with your mouse. Use left and right arrows to select the points and q to exit.