Characterization of Hydraulic Power in Free-Stream Installations

Figure 4

Cross section of an arbitrary ideal hydraulic installation. The water streamtube expands from cross-sectional area to , with a corresponding increase in pressure. The actuator surface of area extracts hydraulic power from the fluid with a resulting pressure drop; the streamtube then expands again so the outlet pressure reaches . The altitudes of the inlet, outlet, and actuator surface do not affect the machine’s performance and are never specified. In this model, neither nor are affected by the power extracted by the device, since it occupies only a small part of the channel.