Merge pull request #601 from adtzlr/change-linear-elastic-largestrain

Change implementation of `LinearElasticLargeStrain` from `NeoHooke` to `NeoHookeCompressible`

CHANGELOG.md

@@ -16,6 +16,7 @@ All notable changes to this project will be documented in this file. The format
 - Use fixed output locations for the extracted field-gradients and the integrated stiffness matrices in `SolidBody` and `SolidBodyNearlyIncompressible`. This enhances the performance.
 - Change default filename in `Mesh.screenshot()` from `filename="field.png"` to `filename="mesh.png"`.
 - Change the return value on job-evaluation from `None = Job.evaluate()` to `job = Job.evaluate()`.
+- Change implementation of `LinearElasticLargeStrain` from `NeoHooke` to `NeoHookeCompressible`.
 
 ### Removed
 - Do not invoke `pyvista.start_xvfb()` on a posix-os. If required, run it manually.

docs/howto/solid.rst

@@ -6,7 +6,7 @@ The mechanics submodule contains classes for the generation of solid bodies. Sol
 Solid Body
 ----------
 
-The generation of internal force vectors and stiffness matrices of solid bodies are provided as assembly-methods of a :class:`fem.SolidBody` or a :class:`fem.SolidBodyNearlyIncompressible`.
+The generation of internal force vectors and stiffness matrices of solid bodies are provided as assembly-methods of a :class:`SolidBody` or a :class:`SolidBodyNearlyIncompressible`.
 
 ..  code-block:: python
 
@@ -47,7 +47,7 @@ The Cauchy stress tensor, as well as the gradient and the hessian of the strain
 Body Force (Gravity) on a Solid Body
 ------------------------------------
 
-The generation of internal force vectors or stiffness matrices of body forces acting on solid bodies are provided as assembly-methods of a :class:`fem.SolidBodyGravity`.
+The generation of internal force vectors or stiffness matrices of body forces acting on solid bodies are provided as assembly-methods of a :class:`SolidBodyGravity`.
 
 
 ..  code-block:: python
@@ -60,7 +60,7 @@ The generation of internal force vectors or stiffness matrices of body forces ac
 Pressure Boundary on a Solid Body
 ---------------------------------
 
-The generation of force vectors or stiffness matrices of pressure boundaries on solid bodies are provided as assembly-methods of a :class:`fem.SolidBodyPressure`.
+The generation of force vectors or stiffness matrices of pressure boundaries on solid bodies are provided as assembly-methods of a :class:`SolidBodyPressure`.
 
 ..  code-block:: python
     

src/felupe/constitution/_models_linear_elasticity_large_strain.py

@@ -18,7 +18,7 @@
 
 import numpy as np
 
-from ._models_hyperelasticity import NeoHooke
+from ._models_hyperelasticity import NeoHookeCompressible
 from ._models_linear_elasticity import lame_converter
 
 
@@ -54,13 +54,12 @@ def __init__(self, E=None, nu=None, parallel=False):
         self.x = [np.eye(3), np.zeros(0)]
 
         mu = None
-        bulk = None
+        lmbda = None
 
         if self.E is not None and self.nu is not None:
-            gamma, mu = lame_converter(E, nu)
-            bulk = gamma + 2 * mu / 3
+            lmbda, mu = lame_converter(E, nu)
 
-        self.material = NeoHooke(mu=mu, bulk=bulk, parallel=parallel)
+        self.material = NeoHookeCompressible(mu=mu, lmbda=lmbda, parallel=parallel)
 
     def function(self, x, E=None, nu=None):
         """Evaluate the strain energy (as a function of the deformation gradient).
@@ -87,10 +86,9 @@ def function(self, x, E=None, nu=None):
         if nu is None:
             nu = self.nu
 
-        gamma, mu = lame_converter(E, nu)
-        bulk = gamma + 2 * mu / 3
+        lmbda, mu = lame_converter(E, nu)
 
-        return self.material.function(x, mu=mu, bulk=bulk)
+        return self.material.function(x, mu=mu, lmbda=lmbda)
 
     def gradient(self, x, E=None, nu=None):
         """Evaluate the stress tensor (as a function of the deformation gradient).
@@ -117,10 +115,9 @@ def gradient(self, x, E=None, nu=None):
         if nu is None:
             nu = self.nu
 
-        gamma, mu = lame_converter(E, nu)
-        bulk = gamma + 2 * mu / 3
+        lmbda, mu = lame_converter(E, nu)
 
-        return self.material.gradient(x, mu=mu, bulk=bulk)
+        return self.material.gradient(x, mu=mu, lmbda=lmbda)
 
     def hessian(self, x, E=None, nu=None):
         """Evaluate the elasticity tensor (as a function of the deformation gradient).
@@ -147,7 +144,6 @@ def hessian(self, x, E=None, nu=None):
         if nu is None:
             nu = self.nu
 
-        gamma, mu = lame_converter(E, nu)
-        bulk = gamma + 2 * mu / 3
+        lmbda, mu = lame_converter(E, nu)
 
-        return self.material.hessian(x, mu=mu, bulk=bulk)
+        return self.material.hessian(x, mu=mu, lmbda=lmbda)

src/felupe/mesh/_mesh.py

@@ -154,7 +154,10 @@ def view(self, point_data=None, cell_data=None, cell_type=None):
         """
 
         return ViewMesh(
-            self, point_data=point_data, cell_data=cell_data, cell_type=cell_type
+            self,
+            point_data=point_data,
+            cell_data=cell_data,
+            cell_type=cell_type,
         )
 
     def plot(self, *args, **kwargs):