1. What is a Coil Heat Exchanger Calculator?

Definition: This calculator determines the heat transfer rate in a coil heat exchanger using the fundamental heat transfer equation.

Purpose: It helps engineers and technicians calculate the thermal performance of coil heat exchangers in various applications.

2. How Does the Calculator Work?

The calculator uses the formula:

Where:

• \( Q \) — Heat transfer rate (Watts)
• \( U \) — Overall heat transfer coefficient (W/m² K)
• \( A \) — Heat transfer area (m²)
• \( LMTD \) — Log mean temperature difference (K)

Explanation: The heat transfer rate is the product of the overall heat transfer coefficient, heat transfer area, and the logarithmic mean temperature difference.

3. Importance of Heat Exchanger Calculations

Details: Accurate heat transfer calculations ensure proper heat exchanger sizing, energy efficiency, and system performance in HVAC, industrial processes, and refrigeration systems.

4. Using the Calculator

Tips: Enter the U-value (typically 10-1000 W/m² K for coil exchangers), heat transfer area, and LMTD. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is a typical U-value for coil heat exchangers?
A: U-values range from 10-1000 W/m² K depending on fluids, materials, and flow conditions. Water-to-water coils typically range 300-1200 W/m² K.

Q2: How do I calculate LMTD?
A: LMTD = [(ΔT1 - ΔT2)/ln(ΔT1/ΔT2)], where ΔT1 and ΔT2 are temperature differences at each end of the heat exchanger.

Q3: What affects the U-value?
A: Fluid properties, flow rates, fouling factors, materials, and heat exchanger design all influence the U-value.

Q4: Can this calculator be used for other heat exchanger types?
A: Yes, the fundamental equation applies to all heat exchangers, though LMTD may need correction factors for some configurations.

Q5: How accurate is this calculation?
A: It provides theoretical maximum performance. Real-world factors like fouling, uneven flow distribution, and heat losses reduce actual performance.