Explain the pros and cons of the Doppler moderator temperature coefficient and coolant void on pwr bwr hwr rmbkgcrlmfbr and msr?

Answer 1

You are asking a lot from Wiki answers. These are senior level nuclear engineering questions. PWR's and BWR's don't control on doppler and use it very little since what doppler does is affect the resonance capture of neutrons by plutonium as they are slowing down. PWR's don't rely on coolant void fraction since the steam voids are only transient on up power manuvers and don't exist steady state. BWR's do rely onthe void fraction to provide negative feedback and simplify control of the reactor. RBMK's do use doppler for control since they are primarily used to convert U238 to Plutonium. I am not familiar with the other reactor types you mentioned. For a better source of nuclear information I suggest that you visit the NIOF website (Nuclear Is Our Future) and follow the links.