Viscosity-Temperature Dependence Models
New viscosity-temperature coupling (viscTempCoupling) has been introduced into the nanoFluidX code as an option. Three models were implemented, polynomial, Sutherland and power law.
- μ0
- Is the reference viscosity.
- T0
- Is the reference temperature.
- S
- Is the Sutherland coefficient.
For air, these values are: μ0 = 1.72 x 10-5Pas, T0 = 273.15 K and S = 110.4.
With n being the exponent. For air, the power law values are: μ0 = 1.72 x 10-5 Pas, T0 = 273.15 K and n = 0.66.
The first thing that needs to be specified is the viscTempCoupling switch in the Simulation parameters section.
Since the viscosity field is updated after establishing the time step, reference viscosity has to be specified in the domain parameter section as ref_visc. The reference viscosity should be the highest expected viscosity during the simulation.