1. What is Fouling Factor?

The fouling factor (R_d) represents the thermal resistance caused by the accumulation of unwanted material on heat transfer surfaces. It quantifies the reduction in heat transfer efficiency due to fouling in heat exchangers.

2. How Does the Calculator Work?

The calculator uses the fouling factor equation:

Where:

• \( R_d \) — Fouling factor (m²K/W)
• \( U_d \) — Dirty overall heat transfer coefficient (W/m²K)
• \( U \) — Clean overall heat transfer coefficient (W/m²K)

Explanation: The equation calculates the additional thermal resistance caused by fouling by comparing the heat transfer coefficients in clean and fouled conditions.

3. Importance of Fouling Factor

Details: Fouling factors are critical for proper heat exchanger design and maintenance. They help engineers account for performance degradation over time and schedule cleaning intervals.

4. Using the Calculator

Tips: Enter both U (clean) and U_d (dirty) heat transfer coefficients in W/m²K. Both values must be positive numbers.

5. Frequently Asked Questions (FAQ)

Q1: What causes fouling in heat exchangers?
A: Common causes include scaling (mineral deposits), particulate accumulation, biological growth, corrosion, and chemical reactions.

Q2: What are typical fouling factor values?
A: Values vary widely (0.0001-0.002 m²K/W) depending on fluid type, temperature, velocity, and service conditions.

Q3: How often should heat exchangers be cleaned?
A: Cleaning frequency depends on fouling rate, which can range from weeks to years. Monitoring pressure drop and temperature effectiveness helps determine optimal intervals.

Q4: Can fouling be completely prevented?
A: While complete prevention is difficult, strategies like filtration, chemical treatment, and maintaining proper velocities can significantly reduce fouling.

Q5: How does fouling affect heat exchanger performance?
A: Fouling reduces heat transfer efficiency, increases pressure drop, and can lead to higher energy consumption and potential equipment failure.