Passive Cooler

The passive heat exchanger (cooler) provides a thermal processing function and is designed and built to be adapted to suit field requirements.


The NOV passive (tubular) heat exchanger is designed to lower production gas temperature for improved service life. The passive heat exchanger (cooler) provides a thermal processing function—i.e., cooling. Heat transfers from the hot medium (gas or liquid) inside a pipe to the less-warm water outside of the pipe. The passive cooler overall dimensions (length, width, and height), pipe dimensions, and stacking configuration are all chosen to amplify natural convection and introduce minor forced convection. The analysis was conducted by iterating between Ledaflow for the internal pipe flow and Ansys CFX for the natural convection currents in the seawater.

The subsea passive cooler has a wide range of product applications, including enhanced subsea gas dehydration and gas/liquid separation, enabled use of low-temperature-rated downstream equipment, and increased compressor efficiency.


  • Lowering production temperature to customers’ needs
  • Field-proven technology
  • Reduced risk for scaling
  • Temperature and pressure monitoring