isotropic elastic bulk modulus, Voigt Reuss Hill bounds
Syntax
[KV,KR,KVRH] = bulkModulus(C)Input
| C | stiffnessTensor | 
Output
| KV | Voigt effective bulk modulus, upper bound | 
| KR | Reuss effective bulk modulus, lower bound | 
| KVRH | Voigt Reuss Hill effective bulk modulus |