Abstract
Some of the major concerns regarding the sewer overflow include serious
environmental, aesthetic and public health problems in receiving water odies. Due to increasing public complains, scientist and engineers are focusing on retention of the entrained sewer solids within the sewer overflow device. Present study investigates the hydrodynamic characteristics of a self cleansing sewer overflow device having a rectangular tank and a slotted ogee weir to capture the gross pollutants. Neither external power source nor mechanical or electrical components are required for the operation of this self-cleansing device. The proposed device is deviated from traditional weir structure in regards to inflow pattern, size and shape. For a traditional weir flow along a creek, the incoming flow is stable without any significant reflection. Whereas, for the proposed weir like device, significant reflections of inflow will occur due to smaller dimension of the device, which needs to be accommodated within existing urban sewerage system. Computational Fluid Dynamics (CFD) technique was used to simulate the flow phenomena. CFD simulated results were compared with analytical results. Results show curved face of the ogee spillway remains in contact with the weir at all low flows. Near the right side of the device, where inflow is being reflected by the side wall, velocity and water level were found much more compared to normal flowing water on the sloping plane. Flow non-uniformity across the weir will hamper effectiveness of self-cleansing, as shear force from uniformly distributed (across the width) flow will effectively remove the trapped pollutants from the screen. Onedimensional analytical solution is unable to produce these flow undulations, which can be easily visualized by 3D CFD simulations.
environmental, aesthetic and public health problems in receiving water odies. Due to increasing public complains, scientist and engineers are focusing on retention of the entrained sewer solids within the sewer overflow device. Present study investigates the hydrodynamic characteristics of a self cleansing sewer overflow device having a rectangular tank and a slotted ogee weir to capture the gross pollutants. Neither external power source nor mechanical or electrical components are required for the operation of this self-cleansing device. The proposed device is deviated from traditional weir structure in regards to inflow pattern, size and shape. For a traditional weir flow along a creek, the incoming flow is stable without any significant reflection. Whereas, for the proposed weir like device, significant reflections of inflow will occur due to smaller dimension of the device, which needs to be accommodated within existing urban sewerage system. Computational Fluid Dynamics (CFD) technique was used to simulate the flow phenomena. CFD simulated results were compared with analytical results. Results show curved face of the ogee spillway remains in contact with the weir at all low flows. Near the right side of the device, where inflow is being reflected by the side wall, velocity and water level were found much more compared to normal flowing water on the sloping plane. Flow non-uniformity across the weir will hamper effectiveness of self-cleansing, as shear force from uniformly distributed (across the width) flow will effectively remove the trapped pollutants from the screen. Onedimensional analytical solution is unable to produce these flow undulations, which can be easily visualized by 3D CFD simulations.
| Original language | English |
|---|---|
| Title of host publication | Proceedings of the 5th Civil Engineering Conference in the Asian Region and Australasian Structural Engineering Conference , held in Sydney, Australia, 8-12 August 2010 |
| Place of Publication | Sydney |
| Publisher | Engineers Australia |
| Pages | 1-6 |
| Number of pages | 6 |
| ISBN (Print) | 9780646537276 |
| Publication status | Published - 2010 |
| Externally published | Yes |
| Event | Civil Engineering Conference in the Asian Region and Australasian Structural Engineering Conference (5th : 2010) - Sydney Duration: 8 Aug 2010 → 12 Aug 2010 |
Conference
| Conference | Civil Engineering Conference in the Asian Region and Australasian Structural Engineering Conference (5th : 2010) |
|---|---|
| City | Sydney |
| Period | 8/08/10 → 12/08/10 |