What is the function of heavy water in a nuclear reaction?

a neutron moderator.

during fission, neutrons are undo from uranium nuclei for example. these neutrons globetrotting too abstain for any thermal energy on be pluck from them. also, abstain neutrons are actually less likely on fission extra uranium nuclei, because a chain reaction is not sustainable.

these neutrons which are travelling at a tenth the rustle connected with light, have on be slowed down via a moderator consisting of 1.light nuclei so that momentum is lengthen out properly and 2.these nuclei are not susceptible to completely collar the neutron. hydrogens in heavy aquatic each enjoy an extra neutron in their nuclei also so are less credible that regular aquatic to absorb an incoming neutron from fission.