sluice valve vs penstock

sluice valve and penstock both are nouns.

Word	Noun	Adjective	Verb	Adverb
sluice valve	Yes	No	No	No
penstock	Yes	No	No	No

As nouns, sluice valve and penstock are synonyms defined as:

sluice valve and penstock: regulator consisting of a valve or gate that controls the rate of water flow through a sluice

Other synonyms of sluice valve include floodgate, head gate, sluicegate, water gate.

sluice valve (noun)	penstock (noun)
regulator consisting of a valve or gate that controls the rate of water flow through a sluice	conduit that carries a rapid flow of water controlled by a sluicegate
	regulator consisting of a valve or gate that controls the rate of water flow through a sluice