Investigation of pressure drop in main air line of pipeline milking system

Objective: The objective of the study is to investigate the pressure drop analytically, numerically and experimentally in the main air line of the pipeline milking system. Material and Methods: The study was carried out in a pipeline milking system, where the main air line consists of a galvanized straight pipe nominally 50 mm in diameter, with one bend. The pressure drops in the pipeline were measured experimentally at different flow rates. In addition, the pressure drops calculated using theoretical equations and determined using various turbulence models with the Computational Fluid Dynamics (CFD). Results: During the experiments, a pressure drop of 0.65 kPa was measured at high flow rates. It was found that the results calculated using the theoretical equations were very close to the experimental data. The lowest MAE and NRMSD values for pressure drops calculated with different CFD turbulence models were found in the Realizable k-ε model. Conclusion: The results showed that the pressure drops in the main air line could be calculated with minor errors by using the numerical analysis method and the Realizable k-ε turbulence model.