What is FLOW NET

Before studying a flow net, the following terms need be clearly understood.


  1. Flow line - the line followed by percolating water through a saturated soil mass under laminar flow conditions, is called flow line .
  2. Equipotential line - the line joining the points of equal hydraulic potentials , is called an equipotential line.
  3. Flow net - the flow net work formed by a system of flow lines and equipotential lines . Is called flow net . A flow net is a pictorial representation of the pattern of flow and the dissipation of hydraulic head causing the flow in soil.
  4. Flow channel - The portion of a flow net bounded by two adjacent flow lines, is called flow channel.
  5. Field - The section of a flow channel located between two adjacent equipotential lines, is called a field 


FUNDAMENTAL CHARACTERISTICS OF A FLOW NET 


  • Flow lines and equipotential lines in a flow net intersect at right angles 
  • All fields formed by equipotential lines and flow lines are approximate squares. 
  • Same quantity of flow occurs through each flow channel 
  • Same potential drop occurs between any two successive equipotential lines 
  • The smaller the dimension of a field , greater is the hydraulic gradient and also velocity of flow .
  • In homogeneous soils, the shape of curves is either clliptical or parabolic. 

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