modelGate_HR
Extends from Icons.Gate (Icons for the gate), OpenHPL.Interfaces.TwoContacts (Model of two connectors).
Information
Background
The Tainter Gate (also known as Radial Gate) is modelled based on a simplified calculation as used in the HEC-RAS simulation software. More specifically the following documentation is taken from the HEC-RAS Hydraulic Reference Manual on Radial Gates.
Implementation
The calculation of the flow through the gate is approximated for three different regions:
Free flowing
$$Q = C_d W T^{T_E} B^{B_E} H^{H_E} \sqrt{2g} \tag{1} $$ (valid for gate opening higher than the downstream water level)
Partially submerged
$$Q = C_d W T^{T_E} B^{B_E} (3H)^{H_E} \sqrt{2g} \tag{2} $$
(valid for the region where the ratio of downstream water level to upstream water level (H_ratio = h_o/h_i) is between 0.67 and 0.8)
Fully submerged
$$Q = C_{dx} A \sqrt{2gH} \tag{3}$$
(otherwise with Cdx being a discharge coefficient tuned for a smooth transition between partially and fully submerged)
Note:
The use of Cdx is different to the implementaion as done in HEC-RAS. This was done in order to have a smoother transition from the partially to fully submerged region.
Parameters
| Type | Name | Default | Description |
|---|---|---|---|
| Type | |||
| Boolean | sluice (from Gate) | false | if true, gate is of type sluice gate, otherwise it is a radial/tainter gate type |
| Geometry | |||
| SI.Height | W | Width of the gated spillway | |
| SI.Height | T | Trunnion height (from spillway crest to trunnion pivot point) | |
| Coefficients | |||
| Real | Cd | 0.7 | Discharge coefficient (typically ranges from 0.6 - 0.8) |
| Real | TE | 0.16 | Trunnion height exponent, typically about 0.16 |
| Real | BE | 0.72 | Gate opening exponent, typically about 0.72 |
| Real | HE | 0.62 | Head exponent, typically about 0.62 |
Connectors
| Type | Name | Default | Description |
|---|---|---|---|
| Contact_i | i (from TwoContacts) | Inlet contact (positive design flow direction is from i to o) | |
| Contact_o | o (from TwoContacts) | Outlet contact (positive design flow direction is from i to o) | |
| Modelica.Blocks.Interfaces.RealInput | B | Height of gate opening [m] |
Components
| Type | Name | Default | Description |
|---|---|---|---|
| Data | data | Using standard class with system parameters | |
| SI.Length | H | h_i | Upstream Energy Head above the spillway crest |
| SI.Height | h_i | Inlet water level | |
| SI.Height | h_o | Outlet water level | |
| SI.MassFlowRate | mdot | Mass flow rate | |
| SI.VolumeFlowRate | Vdot | Volume flow rate through the gate | |
| Real | H_ratio | h_o/h_i | Ratio of outlet to inlet height |