Unit Information
Stokes
The CGS unit of kinematic viscosity, named after George Gabriel Stokes. One stokes is equal to 1 square centimeter per second. Widely used in fluid dynamics and rheology.
Centistokes
A common unit of kinematic viscosity equal to one hundredth of a stokes (10⁻² St). Widely used in engineering for lubricants, hydraulic fluids, and petroleum products.
Conversion Tips
- Remember to check your decimal places for accuracy.
- This conversion is commonly used in international applications.
- Consider the context when choosing precision levels.
- Double-check calculations for critical applications.
Learn More About Viscosity
Scientific Overview
Viscosity is a measure of a fluid's resistance to flow and deformation. It describes the internal friction between adjacent layers of fluid moving at different velocities. High viscosity fluids flow slowly, while low viscosity fluids flow easily.
Historical Background
The concept of viscosity was first studied systematically by Isaac Newton in the 17th century. Jean Léonard Marie Poiseuille made significant contributions to fluid dynamics, and the unit poise is named after him. The modern understanding developed with Stokes and Navier.
Real-World Applications
Lubrication Engineering
Determines the effectiveness of oils and greases in reducing friction.
Food Industry
Affects texture and mouthfeel of products like sauces, creams, and beverages.
Paint and Coatings
Controls application properties and leveling characteristics.
Petroleum Industry
Crucial for pipeline transport and refining processes.
Medical Science
Important for blood flow dynamics and pharmaceutical formulations.
Interesting Facts
- Honey has high viscosity, while water has low viscosity.
- Viscosity generally decreases with increasing temperature for liquids.
- Non-Newtonian fluids change viscosity under stress or over time.
- The pitch drop experiment demonstrates extremely high viscosity.
- Blood viscosity affects cardiovascular health and disease risk.
Key Formulas
Newton's Law of Viscosity
τ = μ(du/dy)Dynamic Viscosity
μ = τ/(du/dy)Kinematic Viscosity
ν = μ/ρPoiseuille's Law
Q = (πr⁴ΔP)/(8μL)Stokes' Law
F = 6πμrv