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Pipe flows and open channel flows in Hydraulics

 

                             PIPE FLOWS

Introduction to Pipe Flow

Introduction

Hydraulics deals with both internal as well as external flow.

Internal flow and External flow:

  • Internal flow is also known as bounded flow. Pipe flow such as water supply system, irrigation system in pipe. Open channel is a part of internal flow.
  • External flow: Fluid flow around turbines, blades, automobiles, building, bridge abutments etc. In both case of flow, no slip condition will take place.

  • A pipe is a closed conduit having circular X-section, used for carrying fluid under pressure. When pipe is running full of liquid, flow is under pressure. 
    • Frictional resistance: Fluid flowing in a pipe is always subjected to resistance due to shear force between fluids particles and the fluid boundary wall of the pipe and between the fluid particles themselves resulting from the viscosity of fluid. So, there is always be loss of energy in the direction of flow which depends on type of flow such as laminar and turbulent flow. 

    • Distinguish between Pipe Flow and Open Channel Flow 

    Fig: HGL and EGL of the pipe flow and open channel flow


    Difference between Pipe Flow and Open Channel Flow

    Difference between Pipe Flow and Open Channel Flow




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