Reply To: Effects of pressure and temperature on a revolving door installed in a building

[peteroznewman]

Hello Sara,

Revolving doors in cold climates often have an edge seal that wipes on a fixed cylindrical surface at the edge of the door to reduce to amount of heat lost to air flowing through what would otherwise be a gap that would leak a lot of air around the edge of the door. The friction between the seal and the surface is probably a significant torque load on the motor that rotates the door.  The cylindrical surface is only on 90 degree sections on the sides next to the wall and there are 90 degree sections that are open to allow people to enter and leave the building through the revolving door. Another significant torque is when the door edge seal goes from the opening to the cylindrical surface. There is also a seal that wipes on the floor and ceiling of the revolving door frame. At least these seals don't have intermittent contact the way the edge seal does.

The forces generated by these seals will be orders of magnitude larger than any pressure differences between the inside and outside air in the building.  The effect of temperature may be to change the stiffness of these seals.  A "brush" style seal may have very little change in stiffness with temperature.