Brazed Plate Heat Exchanger Calculator

Heat Transfer Formula:

\[ Q = U \times A \times LMTD \]

Overall Heat Transfer Coefficient (U):

W/m² K

Heat Transfer Area (A):

m²

Log Mean Temperature Difference (LMTD):

Heat Transfer Rate (Q): W

Unit Converter ▲

Unit Converter ▼

From:	To:

1. What is a Brazed Plate Heat Exchanger Calculator?

Definition: This calculator estimates the heat transfer rate (Q) in a brazed plate heat exchanger based on the overall heat transfer coefficient (U), heat transfer area (A), and log mean temperature difference (LMTD).

Purpose: It helps engineers and technicians determine the thermal performance of brazed plate heat exchangers used in HVAC, refrigeration, and industrial processes.

2. How Does the Calculator Work?

The calculator uses the fundamental heat transfer equation:

\[ Q = U \times A \times LMTD \]

Where:

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

Explanation: The heat transfer rate is directly proportional to the U-value, heat transfer area, and the temperature difference between the hot and cold fluids.

3. Importance of Heat Exchanger Calculation

Details: Proper heat exchanger sizing ensures efficient thermal performance, energy savings, and system reliability in applications like heat pumps, chillers, and industrial processes.

4. Using the Calculator

Tips: Enter the U-value (typically 3000-7000 W/m²K for brazed plate), heat transfer area (from manufacturer specs), and LMTD (calculated from inlet/outlet temperatures). All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What's a typical U-value for brazed plate heat exchangers?
A: U-values typically range from 3000-7000 W/m²K depending on fluid types, flow rates, and plate design.

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: Why are brazed plate heat exchangers efficient?
A: Their compact design creates turbulent flow and high heat transfer coefficients, resulting in excellent thermal performance.

Q4: What affects the U-value most?
A: Fluid properties, flow rates, and fouling factors significantly impact the overall heat transfer coefficient.

Q5: How do I account for fouling?
A: Reduce the U-value by 10-25% depending on fluid cleanliness and expected fouling conditions.