List of symbols
| Symbol | Name of the symbol | Unit |
|---|---|---|
| $A$ | cross-sectional area of the conduit | $\mathrm{m^2}$ |
| $A_1$ | minimum cross-sectional area between upstream face of the gate and upstream wall of the gate chamber | $\mathrm{mm^2}$ |
| $A_2$ | cross-sectional area of the contracted jet issuing from the gap between the downstream face of the gate and the downstream wall of the gate chamber | $\mathrm{mm^2}$ |
| $A_s$ | area of the horizontal projection of the top seal | $\mathrm{m^2}$ |
| $A_{air-pipe}$ | the flow area of the aerated pipeline | $\mathrm{m^2}$ |
| $A_{air}$ | the flow area of the aerated hole | $\mathrm{m^2}$ |
| $B$ | width of the gate | $\mathrm{mm}$ |
| $C_c$ | coefficient of contraction | $\mathrm{ }$ |
| $F_c$ | Froude number | $\mathrm{ }$ |
| $H$ | total head in the reservoir | $\mathrm{m}$ |
| $H_L$ | loss of pressure on the gate | $\mathrm{m}$ |
| $H_v$ | pressure on the gate | $\mathrm{m}$ |
| $K_B$ | coefficient $ K_B $ | $\mathrm{ }$ |
| $K_Q$ | flow coefficient | $\mathrm{ }$ |
| $K_T$ | coefficient $ K_T $ | $\mathrm{ }$ |
| $K_{Qmax}$ | max flow coefficient | $\mathrm{ }$ |
| $L$ | pipe length behind the gate | $\mathrm{m}$ |
| $P$ | downpull force | $\mathrm{kN}$ |
| $P_1$ | downpull resulting from the difference between the pressures acting on the top and bottom surfaces of the gate | $\mathrm{kN}$ |
| $P_2$ | downpull resulting from the pressure differential acting on the horizontal protrusions of the gate | $\mathrm{kN}$ |
| $P_3$ | downpull resulting from the lip | $\mathrm{kN}$ |
| $P_T$ | saturated vapor pressure | $\mathrm{Pa}$ |
| $P_{u}$ | under-pressure behind the gate | $\mathrm{m}$ |
| $Q$ | flow of water before the gate | $\mathrm{m^3/s}$ |
| $Q_p$ | relative flow | $\mathrm{ }$ |
| $Q_{air}$ | air flow | $\mathrm{m^3/s}$ |
| $Q_{max}$ | flow | $\mathrm{m^3/s}$ |
| $T$ | the water temperature | $\mathrm{°C}$ |
| $W$ | force on gate | $\mathrm{kN}$ |
| $a_1$ | width of clearance between upstream face of the gate and upstream wall of the gate chamber | $\mathrm{mm}$ |
| $a_2$ | width of clearance between the downstream face of the gate and the downstream wall of the gate chamber | $\mathrm{mm}$ |
| $b$ | clear width of the conduit at the gate section | $\mathrm{mm}$ |
| $c_{ef}$ | effective closing time factor | $\mathrm{ }$ |
| $d$ | gate thickness | $\mathrm{mm}$ |
| $d^´$ | thickness of the skinplate | $\mathrm{mm}$ |
| $e$ | projection of the skinplate | $\mathrm{mm}$ |
| $e/d$ | ratio $ e/d $ | $\mathrm{ }$ |
| $f_r$ | reduced free flow area in the throttle control system | $\mathrm{ }$ |
| $f_{air}$ | coefficient of under-pressure of aerated hole | $\mathrm{ }$ |
| $g$ | gravitational acceleration | $\mathrm{m/s^2}$ |
| $h$ | gate axis position to sea level | $\mathrm{m}$ |
| $h_c$ | depth of water at vena contracta | $\mathrm{m}$ |
| $p$ | pressure parameter | $\mathrm{ }$ |
| $p_{air}$ | under-pressure in the aerated pipeline | $\mathrm{Pa}$ |
| $p_{a}$ | atmospheric pressure | $\mathrm{Pa}$ |
| $r$ | radius of curvature for the rounding of the gate lip | $\mathrm{mm}$ |
| $s$ | gate opening | $\mathrm{mm}$ |
| $s/s_0$ | gate position | $\mathrm{ }$ |
| $s_0$ | conduit height immediately upstream from the gate | $\mathrm{mm}$ |
| $s_s$ | gate sealing height | $\mathrm{mm}$ |
| $t$ | closing time | $\mathrm{s}$ |
| $v$ | water velocity before the gate | $\mathrm{m/s}$ |
| $v_j$ | velocity in the contracted jet issuing from underneath the gate | $\mathrm{m/s}$ |
| $v_{air}$ | air velocity | $\mathrm{m/s}$ |
| $v_{max}$ | velocity before the gate | $\mathrm{m/s}$ |
| $ΔP$ | water hammer | $\mathrm{m}$ |
| $Δ_h$ | theoretical pressure in the gate at full opening | $\mathrm{m}$ |
| $β$ | aerated coefficient | $\mathrm{ }$ |
| $ζ$ | loss coefficient | $\mathrm{ }$ |
| $θ$ | angle of inclination of the bottom surface of the gate | $\mathrm{°}$ |
| $ρ$ | density | $\mathrm{kg/m^3}$ |
| $ρ_{air}$ | air density | $\mathrm{kg/m^3}$ |
| $σ$ | cavitation number | $\mathrm{ }$ |