Difference between revisions of "Tait Liquid Material"

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Here the zero-pressure bulk modulus  is ''K''<sub>0</sub>. and it has been assumed to be independent of temperature.
Here the zero-pressure bulk modulus  is ''K''<sub>0</sub>. and it has been assumed to be independent of temperature.
This material assumes a Newtonian fluid, which means that the shear stress is given by
Furthermore, the thermal expansion coefficient has been assume to be independent of temperature leading to
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
<math>\tau = \gamma \nabla v</math>


== Material Properties ==
== Material Properties ==

Revision as of 17:03, 30 December 2013

Constitutive Law

This MPM material as a hyperelastic material. The pressure in the liquid is found from the Tait equation:

      [math]\displaystyle{ V(p,T) = V(0,T)\left[1 - C \ln\left(1+{p\over B(T)}\right)\right] }[/math]

where C = 0.0894 is a universal Tait constant, V(0,T) is the temperature dependence of the volume at zero pressure, and

      [math]\displaystyle{ B(T) = { K(0,T)\over C } }[/math]

where K(0,T) is the temperature dependence of the bulk modulus at zero pressure. Defining J as relative volume (i.e., determinant of total deformation gradient) and Jres as determinant of deformation gradient due to free thermal expansion, or:

      [math]\displaystyle{ J = {V(p,T)\over V(0,T_0)} \qquad {\rm and} \qquad J_{res} = {V(0,T)\over V(0,T_0)} = e^{\beta(0)(T-T_0)} }[/math]

where T0 is the stress free temperature and β0 is the zero-pressure thermal expansion coefficient (which has been assumed to be independent of temperature), the constitutive law for pressure is:

      [math]\displaystyle{ p = CK_0\left[\exp\left({1\over C}\left(1 - {J\over J_{res}}\right)\right)-1\right] }[/math]

Here the zero-pressure bulk modulus is K0. and it has been assumed to be independent of temperature.

This material assumes a Newtonian fluid, which means that the shear stress is given by

Furthermore, the thermal expansion coefficient has been assume to be independent of temperature leading to

      [math]\displaystyle{ \tau = \gamma \nabla v }[/math]

Material Properties

Property Description Units Default

History Variables

None

Examples