01919nam a2200205 a 450000100080000000500110000800800410001910000170006024500560007726000470013330000100018050000200019052014050021065000150161565000160163065000230164665300110166965300230168065300100170310760022011-11-11       1974    bl uuuu  m   00u1 u    #d1 aSOUZA, F. de  aNon linear hyorddynamic model of furrow irrigation.  aCalifornia: University of Californiac1974  a172p.  aTese Doutorado.  aA mathematical model of the entire furrow-irrigation process has been developed. This model can be used to analyze and predict the performance of free-draining sloping furrow irrigation systems; capability for prediction of flow with cutback was also provided. The model is based on the solution of the complete continuity and momentum conservation equations, which govern the unsteady, gradually varied flow of water in open channels. Therefore, it is a  complete hydrodynamic model. In addition, it has been demonstrated that zero-inertia conditions can also be simulated by the present model. A fully implicit finite-difference scheme was used to find approximate solutions for the integrated form of the non-linear governing equations, which are simultaneously solved by the double-sweep technique. The input to the model consists of the inflow discharge, furrow slope, cutoff (application) time, length, roughness (the Manning n), soil-infiltration characteristics (k and a in the Kostiakov equation), and furrow shape (C and M in the top width equation, B = CyM, for a power-law cross section). Output information consists of advance and recession times, post-irrigation areal distribution of infiltrated water along the furrow, runoff volume, as well as water application and storage efficiencies. Dimensional analysis was applied to reduce the number of governing parameters in the equations.  airrigation  aIrrigação  aModelo Matemático  aFurrow  aMathematical model  aSulco