Hydraulic dampers and springs Hydraulic dampers and springs We now move from the mechanical domain into the hydraulic domain. In each of these domains we examine systems and the time evolution of these systems. In subsequent years, the word has come to encompass fluids other than water and containers other than pipes. However, in this class we will stick mostly to pipes and to an operating fluid that is incompressible .
Water is a nearly incompressible fluid.
So is hydraulic oil. Systems whose operating fluid is air are called pneumatic . Since our operating fluid is essentially incompressible, the volume of it that is within the system is a constant. The important dynamic variables of the mechanical domain were force and velocity . In the hydraulic domain they are pressure and flow .