The model developed in this research presents effective mechanisms in simulations of a discharge strip understood between the minimum and the maximum allowable values, aiming to determine the relationship between disc...The model developed in this research presents effective mechanisms in simulations of a discharge strip understood between the minimum and the maximum allowable values, aiming to determine the relationship between discharge and water application efficiency, deep percolation and runoff rates, and consequently to optimize the performance of the furrow irrigation systems with continuous flow. The flow applied in each furrow must be adapted to the length, to the field slope and to the nature of the ground. The authors studied the maximum non erosive flow （Q,,,~）, in function of parameters obtained from the dimensions of the furrow, being Pl and/92, respectively, the linear and exponential parameters of the potential functions that described the relationship between the area of the cross section of flow （or wetted perimeter） and height of flow; in this way, the multiplicative effect of,01 on the area of the cross section of flow is linear, while ,02 is exponential. It verified a conjugated effect of,or and p20n the value of Q,,~. The results of this research point out for the importance of having an estimate of the parameters of the geometry of the cross section of flow （,01 and ,02） the most precise as possible, being known that the dimensions of this section can result in impracticable values of Qmax, outside of the acceptable strip in the literature, that is from 1.2 to 4.0 L.sl. This sensibility analysis was also of great benefit to create an interface in the software SASIS, capable to guide the user of this tool in the input of appropriate values for ,01 and P2 to the process of simulation of the irrigation for furrow with continuous flow and of the optimization of its performance.展开更多
文摘The model developed in this research presents effective mechanisms in simulations of a discharge strip understood between the minimum and the maximum allowable values, aiming to determine the relationship between discharge and water application efficiency, deep percolation and runoff rates, and consequently to optimize the performance of the furrow irrigation systems with continuous flow. The flow applied in each furrow must be adapted to the length, to the field slope and to the nature of the ground. The authors studied the maximum non erosive flow （Q,,,~）, in function of parameters obtained from the dimensions of the furrow, being Pl and/92, respectively, the linear and exponential parameters of the potential functions that described the relationship between the area of the cross section of flow （or wetted perimeter） and height of flow; in this way, the multiplicative effect of,01 on the area of the cross section of flow is linear, while ,02 is exponential. It verified a conjugated effect of,or and p20n the value of Q,,~. The results of this research point out for the importance of having an estimate of the parameters of the geometry of the cross section of flow （,01 and ,02） the most precise as possible, being known that the dimensions of this section can result in impracticable values of Qmax, outside of the acceptable strip in the literature, that is from 1.2 to 4.0 L.sl. This sensibility analysis was also of great benefit to create an interface in the software SASIS, capable to guide the user of this tool in the input of appropriate values for ,01 and P2 to the process of simulation of the irrigation for furrow with continuous flow and of the optimization of its performance.
