m_elastic

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m_elastic

Purpose

Material function for elastic solids and fluids.

Syntax

 mat= m_elastic('default') 
 mat= m_elastic('database name') 
 pl = m_elastic('dbval MatId name');
 pl = m_elastic('dbval -unit TM MatId name');

Description

This help starts by describing the main commands of m_elastic : Database and Dbval. Materials formats supported by m_elastic are are then described.

[Database,Dbval] [-unit TY] [,MatiD]] Name

A material property function is expected to store a number of standard materials. See section 7.3 for material property interface.

m_elastic('database Steel') returns a the data structure describing steel.
m_elastic('dbval 100 Steel') only returns the property row.

  % List of materials in data base
  m_elastic info
  % examples of row building and conversion
  pl=m_elastic([100 fe_mat('m_elastic','SI',1) 210e9 .3 7800], ...
    'dbval 101 aluminum', ...
    'dbval 200 lamina .27 3e9 .4 1200 0  790e9 .3 1780 0');
  pl=fe_mat('convert SITM',pl);
  pl=m_elastic(pl,'dbval -unit TM 102 steel')

You can generate orthotropic shell properties using the Dbval 100 lamina VolFrac Ef nu_f rho_f G_m E_m nu_m Rho_m G_m command which gives fiber and matrix characteristics as illustrated above.

The default material is steel.

Subtypes

m_elastic supports the following material subtypes

1 : standard isotropic

Standard isotropic materials, see section 6.1.1 and section 6.1.2, are described by a row of the form

 [MatID   typ   E nu rho G eta alpha T0]

with typ an identifier generated with the fe_mat('m_elastic','SI',1) command, E (Young's modulus), ν (Poisson's ratio), ρ (density), G (shear modulus, set to G=E/2(1+ν) if equal to zero). η loss factor for hysteretic damping modeling. α thermal expansion coefficient. T₀ reference temperature.

2 : acoustic fluid

Acoustic fluid , see section 6.1.3,are described by a row of the form

 [MatId typ rho C eta]

with typ an identifier generated with the fe_mat('m_elastic','SI',2) command, ρ (density), C (velocity) and η (loss factor). The bulk modulus is then given by K=ρ C².

3 : 3-D anisotropic solid

3-D Anisotropic solid, see section 6.1.1, are described by a row of the form

 [MatId typ Gij rho eta]

with typ an identifier generated with the fe_mat('m_elastic','SI',3) command, rho (density), eta (loss factor) and Gij a row containing

 [G11 G12 G22 G13 G23 G33 G14 G24 G34 G44 ...
  G15 G25 G35 G45 G55 G16 G26 G36 G46 G56 G66]

4 : 2-D anisotropic solid

2-D Anisotropic solid, see section 6.1.2, are described by a row of the form

 [MatId typ E11 E12 E22 E13 E23 E33 rho eta a1 a2 a3]

with typ an identifier generated with the fe_mat('m_elastic','SI',4) command, rho (density), eta (loss factor) and Eij elastic constants and ai anisotropic thermal expansion coefficients.

5 : shell orthotropic material

shell orthotropic material, see section 6.1.4, are described by a row of the form

 [MatId typ E1 E2 nu12 G12 G13 G23 Rho A1 A2 TREF Xt Xc Yt Yc S Ge ...
   F12 STRN]

with typ an identifier generated with the fe_mat('m_elastic','SI',5) command, rho (density), ...

6 : Orthotropic material

3-D orthotropic material, see section 6.1.1, are described by a set of engineering constants, in a row of the form

 [MatId typ E1 E2 E3 Nu12 Nu13 Nu23 G12 G13 G23 rho a1 a2 a3 T0 eta]

with typ an identifier generated with the fe_mat('m_elastic','SI',6) command, Ei (Young modulus in each direction), ν ij (Poisson ratio), Gij (shear modulus), rho (density), ai (anisotropic thermal expansion coefficient), T₀ (reference temperature), and eta (loss factor).

See also

Section 4.2.1, section 7.3, fe_mat, p_shell