Here we have as case 1, wire wound fin tube (a special high performance fin tube we make) with no turbulators. In case 2 we have the same wire wound fin tube with internal flexible turbulators. This allows us to see the standalone effect of the turbulators.

1. Number of rows drops from 20 to 12. Total tube length falls from 1164 to 636. This is a 45% decrease.
2. Quite naturally the airside pressure drop falls with its commensurate power savings from 1.2 inches of water column to .8 inches. Evan more remarkably the tubeside pressure drop falls from .5 to .4 kgs per square cm. This demonstrates that though the pressure drop goes up nominally on account of turbulators the actual total pressure drop can actually fall as the number of passes reduce and the length of tube becomes less.