Understanding Kinematic Viscosity
Kinematic viscosity is defined as the ratio of dynamic viscosity to density. It is measured in stokes (St) in the CGS system. To convert kinematic viscosity from stokes to SI units (m²/s), we can use the following relation:
- 1 St = 0.1 m²/s.
Given that the kinematic viscosity of the fluid is 6 stokes:
- Kinematic Viscosity = 6 St = 6 * 0.1 m²/s = 0.6 m²/s.
Specific Gravity and Density
Specific gravity (sp.gravity) is the ratio of the density of a substance to the density of a reference substance (usually water for liquids).
- Given sp.gravity = 2, this means the density of the fluid is twice that of water.
- Density of water = 1000 kg/m³, so the density of the fluid = 2 * 1000 kg/m³ = 2000 kg/m³.
Calculating Dynamic Viscosity
Dynamic viscosity (µ) can be calculated using the relationship:
- µ = Kinematic Viscosity * Density.
Substituting the values:
- µ = 0.6 m²/s * 2000 kg/m³ = 1200 kg/(m·s).
Since 1 N·s/m² = 1 kg/(m·s), we can conclude:
- Viscosity of the fluid = 1200 N·s/m².
Conclusion
The viscosity of the fluid is 1200 N·s/m², derived from its kinematic viscosity and specific gravity. Understanding these conversions is essential in fluid mechanics and civil engineering applications.