Homogeneous and Heterogeneous Reactors

We have been tacitly assuming that the reactors under consideration are what are sometimes known as heterogeneous, in which the fuel, coolant, and moderator if any are distinct physical entities. All reactors used today for power generation are of this form. However, in the early days of nuclear power, there was considerable exploration of an alternative configuration, the homogeneous reactor, defined as a reactor whose small-scale composition is uniform and isotropic 2, p. 378 . Homogeneity...

Types of Nuclear Bomb

Fission Bomb Design

The minimum mass sufficient to sustain a chain reaction is known as the critical mass. This is the mass for which the neutrons produced in fission just balance the neutrons that are absorbed or escape. For an effective nuclear weapon, the critical mass must be assembled quickly. Two general approaches are used to achieve this, as pictured in Figure 17.1 Fig. 17.1. Schematic sketches of fission bomb designs top, gun-type bomb bottom, implosion-type bomb. From Paul P. Craig and John A. Jungerman,...