Hydrodynamics is the study of liquids in motion. Examples of applications include: determining the mass flow rate of petroleum through pipelines, measuring flows around bridge pylons and offshore rigs, ship hull design, optimizing propulsion efficiency, predicting weather patterns and wave dynamics, and measuring liquid metal flows. Benefits of applying hydrodynamics study include: decreased fuel consumption, reduced drag on structures, minimizing noise and vibration, and mitigating unwanted effects, like fouling.
Hydraulics deals with the mechanical properties of liquids, focusing on the engineering uses of fluid properties. Some industrial hydraulic applications include: pipe flow, dam design, pumps, turbines, hydropower, computational fluid dynamics, flow measurement, river channel behavior and erosion. In addition to that, other applications are: heart-valve functions, blood flows, wave dynamics, sedimentation transport, coastal engineering and river hydrology.