anchor.diff:        td Energy head
         td m
       tr
  +      td: var M
  +      td Mach number
  +      td
  +    tr
         td: var m
         td Mass
         td kg
  
positive.code:       td Pa (N m#[sup &minus;2])
      tr
        td #[var Q], #[var q]
        td Heat flow into system / control volume
        td J
      tr
        td: var R
  
negative.code:       td m s#[sup &minus;1]
      tr
        td #[var W], #[var w]
        td Work done by the fluid
        td J
      tr
        td: var &gamma;
  