Reference:

    Figueiredo, R. A., Oishi, C. M., Afonso, A. M., Tasso, I. V. M., &
    Cuminato, J. A. (2016).
    A two-phase solver for complex fluids: Studies of the Weissenberg effect.
    International Journal of Multiphase Flow, 84, 98-115.

In compressibleInterFoam with momentumTransport simulationType set to
twoPhaseTransport separate stress models (laminar, non-Newtonian, LES or RAS)
are instantiated for each of the two phases allowing for different modeling for
the phases.

This example case uses:
- phases "air" and "liquid"
- air phase
  - constant/momentumTransport.air:
    - stress model set to laminar, Newtonian
  - constant/thermophysicalProperties.air:
    - transport set to const (Newtonian)
    - mu (dynamic viscoity) = 1.84e-5
- liquid phase
  - constant/momentumTransport.liquid:
    - stress model set to laminar, Maxwell non-Newtonian
    - nuM (kinematic viscosity) = 0.01476
    - lambda = 0.018225
  - constant/thermophysicalProperties.liquid
    - transport set to const (Newtonian)
    - mu (dynamic viscoity) = 1.46

Liquid phase properties were calculated from the relations given in the paper:
- rho = 890 kg/m^3
- mu = mu_{s} + mu_{p} = 146 poise = 14.6 Pa.s
  s = solvent (Newtonian), p = polymer (Maxwell)
- mu_{s}/mu_{p} = 1/9

=> mu_{s} = 14.6/10 = 1.46 Pa.s
=> nu_{p} = nuM = (9/10)*14.6/890 = 0.01476 m^2/s

compressibleInterFoam solves the energy equation, despite not being needed in
this example.  The case is simply initialised at a uniform temperature of 300K
throughout the domain and at the atmosphere boundary.
