liftup

noun

1. The force that causes an upward flow as part of turbulence.

   “One certainly can argue that not all low-speed streaks lead to liftup, although if the local Reynolds number exceeds the transition limit, it is certain that eventual transition will occur to the hairpin vortex liftup, which ultimately leads to the breakup state.”

   “Each microturbulent event contributes to the wall shear stress; the low-speed streak contributes at the low end with the liftup less than the mean and the sweeps greater than the mean, so that the wall shear stress PDF can be construed as the weighted sum of the individual PDFs.”

   “Near the wall, a Taylor series expansion around y = 0 gives for the liftup:”