Fluid flow direction inside the coil – upward and downward
Introduction In HVAC and refrigeration systems, the direction of fluid flow inside coils critically affects performance, heat transfer, and serviceability. Fin-tube water coils and refrigerant condensers require different flow orientations for distinct physical reasons. Fin-tube water coil — upward flow Problem addressed: Air trapped in tubes reduces heat transfer and creates zones of poor flow. Hydrodynamic reason: Air is much less dense than water and tends to accumulate at high points and corners of the coil. If water flows upward (bottom-to-top), entrained air bubbles...
