The Novel Mechanism of Vibration Effect on Head Loss-Experiment, Simulation and Theory Analysis

As is known to us all, head loss affects the water transmission process, especially under the vibration condition. However, the detailed mechanism of the vibration effect on head loss was unclear, and most studies only focused on the pipeline property and friction itself. In this study, the vibration effect on the head loss mechanism was explored by wettability measurement and Materials Studio (MS) simulation. Iron casting, steel, polyvinyl chloride (PVC), and polyethylene (PE) were chosen as the representative pipeline materials. Different pipelines materials showed different effects on the water drops, and the static contact angles and dynamic contact angles were different. The molecular dynamic simulation results indicated that the water drops showed different interaction energy with pipelines' surfaces, which was the main reason for the head loss. The pipelines' roughness influences the wettability of pipelines, which cause the head loss. The roughness of different pipelines followed the rule: Roughness(iron casting) > Roughness(steel) > Roughness(PVC) > Roughness(PE). The vibration influences the surface roughness, and this fact influences the corresponding fluid flow property, which was widely studied in the previous study. Moreover, the MS results indicated that the vibration affected the solid wettability, which was in accordance with the experimental results, and the vibration altered the internal energy between water drops and pipeline surface. In the end, an economic evaluation was conducted, and the different pipelines' operating costs were compared.

Automated summary

As known, head loss has a significant impact on water transmission, especially under vibration conditions. This study investigated the mechanism of how vibrations affect head loss by measuring wettability and conducting Materials Studio simulations. Different pipeline materials showed varied effects on water drops, and the roughness of the pipelines influenced their wettability, leading to head loss. The molecular dynamic simulation results confirmed that the interaction energy between water drops and pipelines' surfaces was the main cause of head loss, which was affected by vibrations.