conspire/constitutive/solid/hyperelastic_viscoplastic/saint_venant_kirchhoff/
mod.rs1#[cfg(test)]
2mod test;
3
4use crate::{
5 constitutive::{
6 ConstitutiveError,
7 fluid::{plastic::Plastic, viscoplastic::Viscoplastic},
8 solid::{
9 Solid, TWO_THIRDS, elastic_viscoplastic::ElasticViscoplastic,
10 hyperelastic_viscoplastic::HyperelasticViscoplastic,
11 },
12 },
13 math::{IDENTITY_22, Rank2},
14 mechanics::{
15 Deformation, DeformationGradient, DeformationGradientPlastic, Scalar,
16 SecondPiolaKirchhoffStress, SecondPiolaKirchhoffTangentStiffness,
17 },
18};
19
20#[doc = include_str!("doc.md")]
21#[derive(Clone, Debug)]
22pub struct SaintVenantKirchhoff {
23 pub bulk_modulus: Scalar,
25 pub shear_modulus: Scalar,
27 pub initial_yield_stress: Scalar,
29 pub hardening_slope: Scalar,
31 pub rate_sensitivity: Scalar,
33 pub reference_flow_rate: Scalar,
35}
36
37impl Solid for SaintVenantKirchhoff {
38 fn bulk_modulus(&self) -> Scalar {
39 self.bulk_modulus
40 }
41 fn shear_modulus(&self) -> Scalar {
42 self.shear_modulus
43 }
44}
45
46impl Plastic for SaintVenantKirchhoff {
47 fn initial_yield_stress(&self) -> Scalar {
48 self.initial_yield_stress
49 }
50 fn hardening_slope(&self) -> Scalar {
51 self.hardening_slope
52 }
53}
54
55impl Viscoplastic for SaintVenantKirchhoff {
56 fn rate_sensitivity(&self) -> Scalar {
57 self.rate_sensitivity
58 }
59 fn reference_flow_rate(&self) -> Scalar {
60 self.reference_flow_rate
61 }
62}
63
64impl ElasticViscoplastic for SaintVenantKirchhoff {
65 #[doc = include_str!("second_piola_kirchhoff_stress.md")]
66 fn second_piola_kirchhoff_stress(
67 &self,
68 deformation_gradient: &DeformationGradient,
69 deformation_gradient_p: &DeformationGradientPlastic,
70 ) -> Result<SecondPiolaKirchhoffStress, ConstitutiveError> {
71 let _jacobian = self.jacobian(deformation_gradient)?;
72 let deformation_gradient_inverse_p = deformation_gradient_p.inverse();
73 let deformation_gradient_e = deformation_gradient * &deformation_gradient_inverse_p;
74 let left_cauchy_green_inverse_p = deformation_gradient_inverse_p.left_cauchy_green();
75 let (deviatoric_strain, strain_trace) =
76 ((deformation_gradient_e.right_cauchy_green() - IDENTITY_22) * 0.5)
77 .deviatoric_and_trace();
78 Ok(&deformation_gradient_inverse_p
79 * deviatoric_strain
80 * deformation_gradient_inverse_p.transpose()
81 * (2.0 * self.shear_modulus())
82 + left_cauchy_green_inverse_p * (self.bulk_modulus() * strain_trace))
83 }
84 #[doc = include_str!("second_piola_kirchhoff_tangent_stiffness.md")]
85 fn second_piola_kirchhoff_tangent_stiffness(
86 &self,
87 deformation_gradient: &DeformationGradient,
88 deformation_gradient_p: &DeformationGradientPlastic,
89 ) -> Result<SecondPiolaKirchhoffTangentStiffness, ConstitutiveError> {
90 let _jacobian = self.jacobian(deformation_gradient)?;
91 let deformation_gradient_inverse_p = deformation_gradient_p.inverse();
92 let deformation_gradient_e = deformation_gradient * &deformation_gradient_inverse_p;
93 let quantity_1 = deformation_gradient_inverse_p.left_cauchy_green();
94 let quantity_2 = deformation_gradient_inverse_p * deformation_gradient_e.transpose();
95 let scaled_quantity_1 = &quantity_1 * self.shear_modulus();
96 Ok(
97 (SecondPiolaKirchhoffTangentStiffness::dyad_ik_jl(&quantity_2, &scaled_quantity_1)
98 + SecondPiolaKirchhoffTangentStiffness::dyad_il_jk(
99 &scaled_quantity_1,
100 &quantity_2,
101 ))
102 + SecondPiolaKirchhoffTangentStiffness::dyad_ij_kl(
103 &(quantity_1 * (self.bulk_modulus() - TWO_THIRDS * self.shear_modulus())),
104 &quantity_2.transpose(),
105 ),
106 )
107 }
108}
109
110impl HyperelasticViscoplastic for SaintVenantKirchhoff {
111 #[doc = include_str!("helmholtz_free_energy_density.md")]
112 fn helmholtz_free_energy_density(
113 &self,
114 deformation_gradient: &DeformationGradient,
115 deformation_gradient_p: &DeformationGradientPlastic,
116 ) -> Result<Scalar, ConstitutiveError> {
117 let _jacobian = self.jacobian(deformation_gradient)?;
118 let deformation_gradient_e = deformation_gradient * deformation_gradient_p.inverse();
119 let strain = (deformation_gradient_e.right_cauchy_green() - IDENTITY_22) * 0.5;
120 Ok(self.shear_modulus() * strain.squared_trace()
121 + 0.5
122 * (self.bulk_modulus() - TWO_THIRDS * self.shear_modulus())
123 * strain.trace().powi(2))
124 }
125}