Heat transfer characteristics of air flotation dryers

摘要

This paper presents i) a method of measuring experimentally the heat transfer properties of air flotation dryer nozzles: and ii) the heat transfer characteristics of two alternative nozzle designs. It is shown how the heat transfer is affected by the nozzle design, volumetric flow rate and web location, and how the addition of an extra jet at the centre of a conventional two jet nozzle can be used to reduce the fan power without compromising the nozzle's drying capabilities. Results from computational fluid dynamics (CFD) simulations reveal typical nozzle flow temperature distributions and predict heat transfer characteristics that agree well with the experimental findings.