LAUSR

A study was conducted to derive a first estimate of how much hydrogen would be needed to prevent the core from overheating after shutdown and, from this, be able to assess the advantages of using a dedicated decay heat removal system to reduce or eliminate the amount of hydrogen needed to prevent the core from overheating after shutdown. It was demonstrated that the use of such a heat removal system could be needed by certain special nuclear thermal propulsion concepts, such as the fission fragment rocket or the recently proposed pulsed nuclear thermal rocket where significant amplification of specific impulse, along with thrust could be obtained by the direct use of fission fragments or by pulsing the nuclear core.