1. What is a Heat Transfer Coefficient Calculator for Pipe?

Definition: This calculator determines the convective heat transfer coefficient (h) for fluid flow in pipes based on the Nusselt number, thermal conductivity, and pipe diameter.

Purpose: It helps engineers and thermal analysts evaluate heat transfer characteristics in pipe systems.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( h \) — Heat transfer coefficient (W/m² K)
• \( Nu \) — Nusselt number (dimensionless)
• \( k \) — Thermal conductivity of fluid (W/m K)
• \( D \) — Characteristic diameter (m)

Explanation: The Nusselt number represents the ratio of convective to conductive heat transfer, which when multiplied by conductivity and divided by diameter gives the heat transfer coefficient.

3. Importance of Heat Transfer Coefficient

Details: The coefficient is crucial for designing efficient heat exchangers, cooling systems, and thermal management solutions in piping systems.

4. Using the Calculator

Tips: Enter the Nusselt number (from empirical correlations), fluid thermal conductivity, and pipe diameter. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: How do I determine the Nusselt number?
A: Nu is typically calculated using empirical correlations like Dittus-Boelter (for turbulent flow) or Sieder-Tate (for laminar flow) based on Reynolds and Prandtl numbers.

Q2: What's a typical thermal conductivity value for water?
A: Water at 20°C has k ≈ 0.6 W/m K, while at 100°C it's about 0.68 W/m K.

Q3: Does pipe material affect the calculation?
A: No, this calculates the fluid-side coefficient only. Pipe material affects overall heat transfer through wall resistance.

Q4: What's a typical range for h in pipe flow?
A: For water: 300-10,000 W/m² K; for air: 10-100 W/m² K, depending on flow conditions.

Q5: Can this be used for non-circular ducts?
A: Yes, if using hydraulic diameter as the characteristic dimension D.