Diagnostic de fonctionnement d’une rampe frontale adoptée dans une grande exploitation irriguée du Nord-Ouest Tunisien

The objective of this study is to diagnose the field operation of a combined ramp during its first campaign at a large private farm, located in the Borj Elamri delegation, governorate of Manouba (North of Tunisia), to shed light on the quality of the irrigation obtained. This work was devoted to the evaluation of the water distribution, the coefficient of uniformity and possible corrections of the adopted nozzle distribution according to the plan indicated by the manufacturer. On the other hand, we verified conformity between theoretical and actual nozzle plan by placing nozzles at their correct position on the ramp and also tested the uniform distribution of the water. The uniformity tests carried out on the side of the ramp covered a range of prevailing wind speeds of 1 to 6 m/s and a pressure range of 1.6 to 3.5 bars. The operation diagnostics detected that the studied system (pivot-ramp) presented a simple dual-function nozzles (different from the generally used double nozzle plan) with nozzles in good condition with a slight deviation of the flows at the level of the pivot and the front ramp. The linear mode of this system is less wind sensitive and less energy-intensive than the pivot mode. The latter revealed an overall coefficient of uniformity of about 83%, lower than that of the linear mode (86%). Finally, the future use of such a mechanized sprinkler system is not the optimum solution, due in particular to their complexity of design, assembly, operation and use.