Study on plasma enhanced CVD coated material to promote dropwise condensation of steam

The promoting properties of hard coatings with an amorphous hydrogenated carbon basis toattain dropwise concensation (DWC) of steam on coated copper surfaces were investigated. Using differently produced coatings, equilibrium contact angles of theta(eq) of 65, 74 and 90degrees could be reached for water.Stable and well reproducible heat transfer measurements could be performed. For a subcooling temperature of the condensor surface of 5 K. The DWCheat transfer coefficient at the vertical wall is 11 times higher for the surface with theta(eq) = 90 degrees than that measured for filmwise condensation (FWC), seven times higher for thesurface with theta(eq) = 74 degrees and 3.5 times higher for the surface with theta(eq) = 65 degrees.