Above are some typical flow ripple measurements for a power steering vane pump, at low pressure (red) and high pressure (blue). Measurements such as these have proved extremely useful for the design of low noise pumps, and have also been used in the prediction of pressure ripple in power steering systems. Such predictions have been used to assist in the design of low noise systems.

The measured source impedance of this pump is shown below. These measurements are of very high quality, and are accurate over a very broad frequency range. A few 'outliers' are apparent in the data, but the software is capable of identifying and rejecting such points. The source impedance is needed before the pump's flow ripple can be determined, and is also needed for prediction of pressure ripple in circuits.