why Cross shaped contol rods used in boiling water reactor?
thanks in adavance for answer .
The control rods are composed of blades in a shape of cruciform in order to move through the gaps formed between channels of fuel assemblies.
A velocity damper is also provided at the lower portion
of the control rod
to slow down the dropping velocity in case of a accident.
for details one can visit: http://atominfo.ru/files/fukus/npp2.pdf
thank you for your valuable answer .
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