1. What is Water Viscosity?

Water viscosity is a measure of its resistance to flow. The viscosity of water decreases as temperature increases. This calculator provides the dynamic viscosity of water at a given temperature using the empirical Andrade equation.

2. How Does the Calculator Work?

The calculator uses the following equation:

Where:

• \( \mu \) — Dynamic viscosity (Pa·s)
• \( T \) — Temperature (Kelvin)
• 2.414 × 10^-5 — Empirical constant
• 247.8 — Empirical constant (K)
• 140 — Empirical constant (K)

Explanation: The equation models how water viscosity changes with temperature, showing an exponential decrease as temperature increases.

3. Importance of Water Viscosity

Details: Water viscosity is crucial in fluid dynamics, pipe flow calculations, industrial processes, and many engineering applications where water is the working fluid.

4. Using the Calculator

Tips: Enter temperature in Kelvin (must be above 140K for valid results). The calculator provides results in both SI units (Pa·s) and gallon-related units (lb-s/ft²).

5. Frequently Asked Questions (FAQ)

Q1: What is the temperature range for this equation?
A: The equation is valid for liquid water, typically between 273K (0°C) and 373K (100°C), though mathematically it works above 140K.

Q2: Why provide results in lb-s/ft²?
A: This unit is commonly used in American engineering calculations involving gallons and fluid flow in pipes.

Q3: How does viscosity affect flow rate?
A: Higher viscosity means greater resistance to flow, requiring more pressure to maintain the same flow rate through a pipe.

Q4: Does this account for water purity?
A: No, this is for pure water. Dissolved salts or other substances will change viscosity.

Q5: How accurate is this equation?
A: It's reasonably accurate for most engineering purposes, though more complex equations exist for precise scientific work.