Study of Flow Around Developed Permeable Pile Groyne

Scouring and erosion commonly occur to form river morphology. This process could become a disaster if not managed properly. One of the solutions to this problem is controlling river flow and bed changes using groyne construction. Researchers have been studying the structure of groynes for decades, specifically focusing on the permeable pile groyne. In this study, the stability of the structure was considered to develop four models of permeable pile groynes, which were then compared with pile groyne models based on the Indonesia National Standard. Flow patterns and surface water elevation were mathematically investigated. The results show that the deceleration of velocity downstream of pile groynes can be controlled by adjusting the pile spacing. Three types of pile spacing in a group of groynes, (i.e., parallel to the flow, perpendicular to the flow, and oblique to the flow), significantly affect the flow pattern. Permeable pile groynes adhering to the Indonesian standard demonstrated reduction in velocity up to 83.68%. Meanwhile, the developed model M5 achieved velocity reductions of 72.64%. Model M5 is anticipated to be more stable due to higher permeability and the number of pile groups against with the lateral force. Consequently, this model could serve an alternative to the Indonesia National Standard for groyne design.