What is fluid mechanics?

Fluid mechanics is the study of how liquids and gases behave and interact with forces — essential for designing pipes, pumps, aircraft, ships, and ventilation systems.

Exam tip: keep SI units consistent end-to-end, write the governing relation symbolically before substituting, and sanity-check magnitude and sign.

Understand the concept

Fluids include both liquids (water, oil) and gases (air, steam). Fluid mechanics covers static fluids (fluid statics) and moving fluids (fluid dynamics), including pressure, buoyancy, viscosity, and turbulence.

Key concepts

Engineers work with continuity (mass conservation), momentum equations, and energy equations along streamlines. Reynolds number helps predict laminar vs turbulent flow. Boundary layers and drag matter for vehicles and ducts.

Applications

Piping networks, water supply, oil and gas pipelines, HVAC ducting, hydraulic machinery, ship hulls, wind turbines, and blood flow in biomedical devices all require fluid mechanics.

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