Investigation of the stability of a hydraulically controlled float tank/flap gate weir, rigidly connected by a shaft, in a rainwater drainage pipe system
Abstract
Rainwater runoff control in a mixed storm drain/sewer system was investigated. Fixed side weir outlets to a spillway were found unsatisfactory. A self-regulating float chamber/flap gate on an eccentric pivot was designed. With this type of construction, the spillway fills only in case of very heavy flooding. Lighter runoff is stored in the pipe network until it can be processed through the sewage treatment plant. Functional criteria by which this control system can be evaluated were sought. With respect to stationary boundary conditions the functional relationships between the limiting hydraulic quantities were studied theoretically and experimentally. Operating conditions are simulated by a numerical model in which the hydraulic quantities are assumed to be stationary within a time step. For any existing type of rainwater outlet construction, having a float chamber/flap gate system, this numerical method permits computation of the highest level of outlet, the point of equilibrium of the inflow and spilloff, the water surface, and the generating angle of the rainwater outlet construction. As an alternative, the points of equilibrium can also be determined iteratively by using dimensioning graphs.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- February 1982
- Bibcode:
- 1982STIN...8227704B
- Keywords:
-
- Automatic Control Valves;
- Dimensional Stability;
- Drainage;
- Pipes (Tubes);
- Sewers;
- Floats;
- Flood Control;
- Gates (Openings);
- Structural Design Criteria;
- Water Runoff;
- Fluid Mechanics and Heat Transfer