A hyperelastic constitutive model for compression stiffening applicable to brain and fat tissues
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چکیده
2 Reformulate the free energy functions W(λ1, λ2, λ3) for the Neo-Hookean, MooneyRivlin, and Fung materials in Table 1 in terms of the invariants of b as W(Ib 1 , I b 2 , I b 3). Remember that for an incompressible material, J = 1, and thus λ3 = 1/(λ1λ2). 3 For the free energy functions W(Ib 1 , I b 2 , I b 3) of the Neo-Hookean, Mooney-Rivlin, and Fung materials (from 2), calculate the derivatives β1 = 2 ∂W/∂I1 and β−1 = −2 ∂W/∂I2.
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