Material Input Page
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The first tab on the GUI gives the material definition page.  A minimum of one material must be defined to obtain a solution.  Any number of materials can be defined, even if all of the materials are not actually used in cylinder definitions.  Each material definition requires five input parameters: the name, elastic modulus, Poisson ratio, thermal expansion coefficient  (CTE), and density.  The name for each material must be unique and can have up to 10 characters.  The computed shear modulus and bulk modulus for each material are also displayed.  Figure 5 shows the material dialog page.  Click on the figure for additional information. 

Material Tab Name (10 Characters Max) Elastic Modulus Poisson Ratio Thermal Expansion Coefficient Density Shear Modulus (Output) Bulk Modulus (Output) Number of Materials

Figure 5.  Material Definition Dialog Page

An isotropic material requires only two mechanical properties to define its elastic behavior.  The two properties required by Concyl are the elastic modulus and the Poisson ratio.  The other required material properties are the CTE and the density.  The CTE relates the thermal strain to the applied temperature, and the density is used to compute the cylinder mass.  The table below summarizes the properties required to define each material and the base units for each property. 

Table 1.  Required Material Input

Parameter
GUI Name
Units
Example Units
Elastic Modulus
E
F/L2
psi, Pa
Poisson Ratio
nu
unitless
-
CTE
Alpha
Temp-1
/°F, /°C
Density
rho
M/L3
lb/in3, kg/m3

Applicable Base Units:
F = force
M = mass
L = length
H = temperature
T = time

For isotropic materials, the shear modulus (G) and bulk modulus (K) are related to the elastic modulus (E) and Poisson ratio (n) by the following formulas:

graphic,  graphic
These formulas reveal that the Poisson ratio has an allowable range of -1 to 0.5.  The 0 value corresponds to a perfectly compressible material, and the 0.5 value corresponds to a perfectly incompressible material. 

The user can choose any units when entering the material properties.  However, great care must be taken to ensure that the material property units are mutually consistent and also consistent with the units used to specify the applied loads.  For example, if the elastic modulus units are psi, then the density units must be lb/in3, and the applied pressure load units must also be psi. Likewise, the radial dimensions of the cylinders must be entered in inches for consistency.