Forced Draft Dry Cooler
What is a Forced Draft Dry Cooler?
A Forced Draft Dry Cooler is defined by the placement of its fan on the intake (inlet) side of the heat exchanger coil. In this design, the fan pushes or forces ambient air through the coil, creating a positive pressure on the upstream side of the finned-tube bundle.
This is the direct opposite of an Induced Draft cooler, where the fan pulls air through the coil.
How It Works: The Forced Draft Principle
- Air Intake: The fan, mounted at the air inlet, draws ambient air directly into the unit.
- Pushing Air Through the Coil: The fan acts like a pressurizing unit, forcing air through the heat exchanger coils.
- Heat Transfer: As the air is pushed across the fins, it absorbs heat from the process fluid inside the tubes (sensible heat transfer).
- Low-Velocity Discharge: The now-warmed air exits the coil at a relatively low velocity and is discharged from the unit, typically through louvers or simply by escaping the pressurized plenum.