text: Another use is in the estimation of gas holdup in a bubble column. In a bubble column, the gas holdup (fraction of a bubble column that is gas at a given time) can be estimated by:
  where:
  * is the gas holdup fraction
  * is the Eötvos number
  *  is the Froude number
  *  is the diameter of holes in the column's spargers (holed discs that emit bubbles)
  *  is the column diameter
  * Parameters  to  are found empirically