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Objective: The objective of this study was to investigate the effect of different pipe wall thickness on the flow rate of cylindrical type integrated emitters used in drip irrigation pipes. Material and Methods: Cylindrical in-line integrated type, non-pressure compensated two drip emitters were considered within the scope of this work. The drip emitters (E1 and E2) manufactured by two different companies were integrated in 1.1, 0.9 and 0.6 mm wall thickness pipes. The emitter flow rate measurements were carried out at five different pressure levels for all drip irrigation pipes. Results: The operating pressure and flow rate relationships for the emitters and drip irrigation pipes at each pipe wall thickness were also determined. In general, it was also observed that when the wall thickness decreased sequentially from 1.1 mm and 0.9 to 0.6 mm, average emitter flow rate increased about 30% based on the brand of the emitter as well as on pressure. The variation of emitters flow rate based on the wall thickness at the nominal pressure of 100 kPa was analyzed statistically. Based on the results, these variations were found statistically significant (P, Amaç: Bu çalışma, aynı tip damlatıcının farklı et kalınlığına sahip damla sulama borularına entegre edilmesi durumunda, damlatıcı debisi üzerine etkilerini ortaya koymak amacıyla yapılmıştır. Materyal ve Metot: Çalışmada iki farklı firma tarafından imal edilen türbülanslı akış rejimine sahip, boru içine entegre, silindirik tip, basınç dengeleyici özelliği olmayan damlatıcılar ele alınmıştır. İki farklı firma tarafından imal edilen damlatıcılar (E1 ve E2) 1.1, 0.9 ve 0.6 mm et kalınlığına sahip borulara yerleştirilmiştir. Damlatıcı debi ölçümleri beş farklı basınçta gerçekleştirilmiştir. Denemeler sonucunda, her bir boru et kalınlığındaki damlatıcı ve damla sulama borusu için basınç-debi ilişkileri ortaya konulmuştur. Bulgular: Genel olarak boru et kalınlığının 1.1 mm’den, 0.9 mm’ye ve en düşük değer olan 0.6 mm’ye düşmesi durumunda, üretim yapan firmanın damlatıcısına ve deneme basıncına göre %30’lara varan oranlarda artış meydana geldiği gözlenmiştir. Çalışma kapsamında, 100 kPa nominal çalışma basıncında damlatıcı debilerinde, et kalınlığına bağlı olarak meydana gelen bu değişim değerleri istatiksel yönden araştırılmış ve Duncan istatistik analiz sonuçlarına göre damlatıcı debilerinde meydana gelen değişimin E1 ve E2 marka damlatıcılı damla sulama borularının tümünde istatistiksel olarak önemli (P

EgeUn###, The objective of this study was to predict total friction losses in drip irrigation laterals with cylindrical integrated in-line emitters at different spacing using Computational Fluid Dynamics (CFD) simulation method. Two types of drip irrigation laterals with different technical specifications were used in the study. In the laboratory, the total friction losses were measured in the laterals for different velocities. In CFD analysis, standard k-epsilon, RNG k-epsilon, realizable k-epsilon, Reynolds Stress (RSM) with Linear Pressure-Strain (LPS) turbulence models and standard wall function, non-equilibrium wall function, enhanced wall treatment were considered. CFD simulation results were compared with experimental total friction losses in laterals. The highest prediction was obtained by RSM turbulence model with LPS using standard wall function with the lowest values of MAPF (2.96%) and RMSE (369 Pa).

The objective of this study was to determine the hydraulic properties of a flat type emitter using Computational Fluid Dynamics with different turbulence models and model options. in addition, it is aimed to investigate the effects of the emitter hydraulic properties on the design when the same emitter is used in drip irrigation pipes with different wall thicknesses. the lowest mean percentage deviation between the measured flow rates and the calculated flow rates with turbulence models was found as 0.70% and 0.74% in the SST k-omega and Stress-Omega RSM turbulence model for the wall thickness of 0.25 mm pipe, respectively. Also, the mean percentage deviation for the laminar turbulence model was found to be -1.01%. the minimum MAE (0.021 L h(-1)) and RMSE (0.028 L h(-1)) values were found in the SST k-omega low-Re corr. turbulence model and the minimum MAPE (1.068%) was found in the laminar turbulence model.