Abstract: This paper studies equilibrium liquid level formed by the rotation of liquid on the

wall，the equation is deduced when the slop of the wall is K ( K≠0) . When K→∞ ，the change of liquid

level is infinite with the in- crease of rotating speed，but the rise height of liquid level is

equal to the fall depth of liquid level，and the volume relationship is a constant. when K>0，the

container is a round table with large top and small bottom. The liquid level

change caused by rotating paraboloid is limited，and the limit value is槡3 +1，when the liquid

rotation angular veloci- ty exceeds the critical angular velocity，the rotating liquid surface

is divided into two parts: the paraboloid in the middle and the water film with growing edge.

Key words: fluid mechanics, wall rotation, equilibrium liquid level, identity, critical value