Fission Power Density Distribution

The heat transfer analyses were based upon the material and geometry specifications described in Sects. 2 and 3. However, because the fission/power density distribution was not available at the onset of these analyses, the following simplistic bounding parametric assumptions were specified ... 

The detailed features of the chain reaction are determined by the various nuclear processes which can occur between the free neutrons and the materials of the reactor system. As in chemical chain reactions, the rates of the reactions involved in the chain are directly dependent upon the density of the chain carrier, in the present case the neutrons. Thus in order to determine the various properties of a reactor, such as the power-production rate and the radiation-shielding requirements, it is necessary to obtain the fission reaction rate throughout the system and, therefore, the neutron-density distribution. In fact, all the basic nuclear and engineering features of a reactor may be traced back ultimately to a knowledge of these distribution functions. 

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