Jet flow behaviour at rigid vegetation layer

Objective: The behavior of the submerged jet flow in the region of rigid submerged vegetation was investigated in this study. The obtained results were compared with the free submerged jet flow results. Material and Methods: In this study, vegetation was simulated using plexiglass rods with a diameter of 1 cm and heights of 5 and 10 cm. Two different vegetation densities were selected; which are low density vegetation (1=0.01 - N1=172 IP/m2) and high-density vegetation (2=0.08 - N2=1142 IP/m2). In the experiments, velocity measurements were made with a 3D Down Looking Probe and 3D Acoustic Doppler Velocimeter-ADV. Results: In this research, the time average velocity profiles were examined in the flow direction, lateral direction and vertical direction. The results showed that especially high-density vegetation effected in damping the submerged jet flow. Furthermore, vegetation with smaller high showed a similar behavior to the unobstructed jet flow conditions. In addition, it was determined that the submerged jet flow lost its effectiveness after a distance of four times the nozzle jet diameter in the lateral direction. Conclusion: The results obtained in this study showed that especially high-density vegetation and higher-height vegetation had serious effects on the distribution of the jet flow. It has been determined that parameters such as plant density and plant height are very important for the distribution of wastewater in the aquatic environment.