Theoretical Framework and Governing Parameters

The viscosity estimation of liquid metals in this study is based on a theoretical framework that employs dimensionless modeling principles to describe momentum transport at the atomic scale. By normalizing thermophysical properties with respect to characteristic energy and length scales, a generalized representation of liquid metal behavior can be achieved. This approach is particularly suitable for high–melting-point metals such as niobium, where experimental viscosity data at elevated temperatures is scarce.

The model begins with the calculation of the number density (n), which represents the degree of atomic packing within liquid niobium. Number density is determined using the metal density (ρ) and atomic weight (M):