01284naa a2200205 a 450000100080000000500110000800800410001910000140006024500490007426000090012352007470013265000150087965000150089465000160090965000160092565300130094165300140095470000210096877300890098910718712009-06-18       1985    bl ---       0--  u    #d1 aRAYEJ, M.  aFurrow irrigation simulation time reduction.  c1985  aTemporal and spatial changes in the flow profile decrease with time under furrow irrigation, and these slow changes suggest modifications inthe simulation methods. Geometrically increasing time steps and node deletion at the upstream boundary are introduced and evaluated for accuracy and CPU time reduction. Increasing the time steps reduced CPU time without sacrificing accuracy significantly in predicting edvance. The geometric progression factor is estimated automatically from the first two advance increments, thus incorporating site-specific flow and infiltration characteristics. The moving left boundary method is slightly more accurate, but is less cost-efficient than the varying time-step modification for the example conditions.  airrigation  aComputador  aHidráulica  aIrrigação  aComputer  aHydraulic1 aWALLENDER, W. W.  tJournal of Irrigation and Drainage Engineeringgv. 111, n. 2, p. 134-146, june 1985.