عنوان مقاله [English]
نویسندگان [English]چکیده [English]
Models can be calibrated using suitable field data. A coupled volume balance–zero inertia (VB-ZI) model increases the accuracy of advance distance estimation in furrow irrigation. Surface storage volume in VB-ZI model was estimated using a power function. In this research the subsurface storage in furrow irrigation was calculated using the corrected Hall technique and a modified VB-ZI model (MVB-ZI) was developed. The developed model uses the momentum term of the ZI model. For evaluation of the MVB-ZI accuracy in furrow irrigation, three data series in different field conditions were used. The collected field data were hydraulics and geometric coefficients of cross section, advance time, inflow and outflow discharge, Manning’s coefficient, furrow bed slope and infiltration coefficients. The root mean squared error (RMSE) index, coefficient of residual mass (CRM) index and model efficiency (ME) index were used to evaluate the model. The RMSE values for the MVB-ZI model were ??.??, ??.?? and ??.?? for data series ?, ? and ?, respectively. The calculated values for VB-ZI model were ??.??, ??.?? and ??.??. The CRM values for field data series ?, ? and ? were ?.???, ?.??? and ?.???, respectively which indicate the MVB-ZI model overestimation. The results show that the MVB-ZI model accuracy in estimating advance distance in furrow irrigation is greater than that of the VB-ZI and VB models. Therefore, the use of MVB-ZI model is recommended because of its simplicity and accuracy compared with VB-ZI and VB models.