Node or Pit: Since Build 2005-05-AN, sets the height contraction coefficient of a R pit channel.
Prior to Build 2005-05-AN, not used.
R Channel_Type: The height contraction coefficient for orifice flow at the inlet. Usually 0.6 for square edged entrances to 0.8 for rounded edges. If value exceeds 1.0 or is less than or equal to zero, it is set to 1.0.
Not used for unsubmerged inlet flow conditions or outlet controlled flow regimes. Not used for C channels.
