Cauchy Number Calculators

1. Cauchy Number (Ca)

To calculate the Cauchy Number, you need the following:

Where:

• ρ = Density of the fluid (kg/m³)
• u = Flow velocity (m/s)
• L = Characteristic length (m)
• σ = Surface tension of the fluid (N/m)

What you need to provide:

• Density ρ
• Flow velocity u
• Characteristic length L
• Surface tension σ

---

2. Bulk Modulus of Elasticity (K)

The formula for Bulk Modulus is:

Where:

• V = Initial volume (m³)
• ΔP = Change in pressure (Pa)
• ΔV = Change in volume (m³)

What you need to provide:

• Initial volume V
• Change in pressure ΔP
• Change in volume ΔV

---

3. Density (ρ)

Density can be calculated using:

Where:

• m = Mass (kg)
• V = Volume (m³)

What you need to provide:

• Mass m
• Volume V

---

4. Flow Velocity (u)

Flow velocity is calculated using:

Where:

• Q = Flow rate (m³/s)
• A = Cross-sectional area (m²)

What you need to provide:

• Flow rate Q
• Cross-sectional area A