It can be seen from the Figure 4, that the region near the closed valve is subject to a strong cavitation, accompanied by a decrease in pressure and an increase of the
relative velocity between the phases.
Based on the velocity triangle, the
relative velocity of the fluid was determined when it tangentially passes by the blades at the impeller inlet and outlet.
In the present work, we shall use a Coulomb model where the slip force does not depend on the
relative velocity, and it is equal to the limit value [T.sub.sMax].
(iv) The calculation of the
relative velocity between phases with (9).
The maximum control input [u.sub.max] is set to [u.sub.max] = 0.1 m/[s.sup.2], and the maximum
relative velocity [v.sub.max] is set to [v.sub.max] = (0.5,0.5,0.5,0.5,0.5,0.5)T m/s.
and its time derivative is
relative velocity (11b).
In the action point model firstly developed by Michaels [18], drivers perceived
relative velocity according to the changes on the visual angle subtended by the lead vehicle.
since in the frame of the rotating clocks they have no
relative velocity wrt each other.