Editing Sluice (section)

==Types of sluice gates==
{{Unreferenced section|date=May 2025}}{{main|Gate valve}}
[[File:Vannsluse.svg|thumb|Plan view of a fan sluice (flow from bottom to top of diagram) (Note: gray areas are the inner empty spaces in which water can flow.)<br />1: Tube connecting the chamber to the high water side of the sluice <br />2: Gates to regulate the water level in the chamber. Only one gate may be opened at a time <br />3: Tube connecting the chamber to the low water side of the sluice <br />4: The chamber in which the water level can be controlled <br />5: Door with larger surface <br />6: Door with smaller surface. <br />When the tube to the high water level side (1) is opened, the water level in the chamber (4) will rise to this same level. As there is no height difference across the larger gate (5), it exerts no force. However, the smaller gate (6) has a higher level on the upstream side, which exerts a force to close the gate (counter-clockwise). When the tube to the low water side (3) is opened, the water level in the chamber (4) will fall, and a force will be exerted on the large door (5) in the opening direction (clockwise). The pressure difference on both doors is the same, but the surface area is not. This ensures that the opening force (on 5) overcomes the closing one (on 6), which causes the gate to turn clockwise and open.|303x303px]]
; Flap sluice gate: A fully automatic type,  controlled by the pressure head across it; operation is similar to that of a [[check valve]]. It is a gate hinged at the top. When pressure is from one side, the gate is kept closed; a pressure from the other side opens the sluice when a threshold pressure is surpassed.
; Vertical rising sluice gate: A plate sliding in the vertical direction, which may be controlled by machinery.
; Radial sluice gate: A structure, where a small part of a cylindrical surface serves as the gate, supported by radial constructions going through the cylinder's radius. On occasion, a counterweight is provided.
; Rising sector sluice gate: Also a part of a cylindrical surface, which rests at the bottom of the channel and rises by rotating around its centre.
; Needle sluice: A sluice formed by a number of thin needles held against a solid frame through water pressure as in a [[needle dam]].
; Fan gate: ({{langx|nl|waaiersluis}}) This type of gate was invented by the Dutch [[Hydraulic engineering|hydraulic engineer]] {{ill|Jan Blanken|nl}} in 1808. He was Inspector-General for ''Waterstaat'' ([[Water resource management]]) of the [[Kingdom of Holland]] at the time.<ref>{{cite book|author=Blanken J. Jz.|title=Nieuw ontwerp tot het bouwen van minkostbare sluizen, welke alle de vereischten der bekende sluizen bezitten, en daarenboven de steeds ontbrekende, meer uitgebreide nuttigheden van dezelve vervullen kunnen|date=1808|language=nl}}; {{cite book|author=Goudriaan, Adrianus Franciscus|title=Verhandeling over het ontwerp van sluizen, volgens de uitgave van den heer inspecteur generaal bij den waterstaat van het Koningrijk Holland, J. Blanken Jansz., het eerste aan de Benschopper Sluis beproefd: opgesteld ter aanleiding tot eene naauwkeurige overweginge van hetzelve, in vergelijking met zijnen over dit onderwerp gedrukten brief, en het antwoord door eerstgenoemden daar op uitgegeven|date=1809|publisher=Van Esveldt-Holtrop|place=Amsterdam|language=nl}}</ref> The fan door has the special property that it can open in the direction of high water solely using water pressure. This gate type was primarily used to purposely [[Inundation|inundate]] certain regions, for instance in the case of the [[Hollandic Water Line]]. Nowadays this type of gate can still be found in a few places, for example in [[Gouda, South Holland|Gouda]]. A fan gate has a separate chamber that can be filled with water and is separated on the high-water-level side of the sluice by a large door. When a tube connecting the separate chamber with the high-water-level side of the sluice is opened, the water level, and with that the water pressure in this chamber, will rise to the same level as that on the high-water-level side. As there is no height difference across the larger gate, it exerts no force. However the smaller gate has a higher level on the upstream side, which exerts a force to close the gate. When the tube to the low water side is opened the water level in the chamber will fall. Due to the difference in the surface areas of the doors there will be a net force opening the gate.