تدوين الگوريتم دو مرحله اي بهينه سازي اقتصادي سيستم هاي آبياري تحت فشار

Development of a Two-Stage Economic Optimization Algorithm for Pressurized Irrigation Systems

Some of common hydraulic methods for designing pressurized irrigation systems are: (/) unit head loss method, (//) (maximum allowable) velocity method, and (///) percent head loss method. In this research, a two- stage economic optimization algorithm was introduced to design pressurized irrigation systems and was developed in LINGO programming environment. Results obtained by this model were compared with the ones from the foregoing hydraulic methods for a hypothetical sprinkle irrigation system comprised of 3 manifolds to assess the performance of the new algorithm. The results showed that this optimization algorithm resulted in 3% lower costs for a small irrigation system and favorable distribution uniformity. Also it was concluded that system design according to unit head loss method with maximum 0.01 m.m"1 head loss resulted in the highest distribution uniformity in comparison to the other methods and the optimization algorithm, unit head loss method with maximum 0.02 m.m"1 head loss and maximum allowable velocity method followed it. The standard deviation of the sprinklers outflow values as compared to the namely outflow value were estimated 0.1, 0.03, 0.05 and 0.12 lit.sʹ1 for the optimization method, unit head loss method with maximum 0.01 m.m"1 head loss, unit head loss method with maximum 0.02 m.mʹ1 head loss, maximum allowable velocity method, respectively.