We keep ours running 24/7 except when a family member shuts them off (and gets yelled at). We have high ceilings which comes into play in the winter due to heat layers as mentioned. The heat transfer analysis provided only considered conduction (heat trasferred by contact of two surfaces) and not convection (heat transfer by actually moving the air).
When the blades rotate clockwise, air is being pulled down from the ceiling and concentrated into the center of the room. Concentration of the air increases velocity and provides more cooling effect. We usually run our fans on medium to high in the summer.
When the blades rotate counter-clockwise, air is being drawn up from the floor in the center of the room and dispersed across the ceiling and down the walls. Dispersal of the air decreases velocity so the cooling effect of air movement is less noticeable in the winter season. Dispersal of the air is due to distance from fan to ceiling (vs distance to floor). We run our fans on low in the winter.....extra low would be better if there was such a setting.
with no reasonable expectation for ER, I'm just here auditing the AP class.Retired 8/1/15.