Numerical Study of The Sensitivity of Intake Structures to Deficient or Excess Water Removal Under Unsteady Flow Condition

Variation of intake hydraulic conditions and channel flow discharge cause unsteady flow in irrigation network. To evaluate the performance of the function of the intake structures, study of their hydraulic characteristic is necessary. Therefore in present study a computer model has developed in which the unsteady flow equations (Saint-Venant equation) have been disceretizied using finite difference and Crank-Nicolson method. Water surface elevation at any junction is calculated applying matrix properties and influence line technique implicitly. Different kinds of control structure such as intake and check structures have been introduced to model as internal boundary condition. Combining energy and momentum equations (E-M method) the flow from the gate of check structure at every time steps is calculated. After model verification, the main channel of the Miandarband irrigation network with 27 kilometer length from 15 to end with five radial gates check structures, seventeen turnout structures and five Neyrpic intake was simulated and different kind of optional performance have been studied.