Feasibility Study of a Pulsed Thermonuclear Reactor

摘要

The minimal conditions of burning time, plasma temperature, and number density yielding net energy balance in a pulsed reactor are investigated. The analogue of a θ pinch is considered in which a long cylinder of β = 1 plasma is contained by a magnetic field, furnished by a single turn coil. The basic energy losses are joule heating of the coil by the magnetic field, heating of the coil by neutrons as they pass through it to the neutron blanket, and bremsstrahlung. The basic energy source is kinetic energy of the neutrons from d-t fusion reactions. Fuel burnup and α-particle heating of the plasma are also considered. Heat is removed from the beryllium-copper coil by means of turbulent flow of supercritical H2O in channels. A coil temperature of ~ 500 ℃is consistent with the requirements of supercriticality of the H2O. The energy required for pumping the heat-transfer coolant is taken into account in the energy balance. Two basic electrical models of the pulsed reactor are taken. In the first, all of the magnetic field B is furnished by the coil. In the second, the sustained-field θ pinch, a steady magnetic field is suddenly pulsed off by an opposite magnetic impulse of short duration. For B = 200 kG the minimum burning times TT in the two cases are about 15 and 1.5 msec, respectively. The nT product in the first case is about 10 times that of the Lawson criterion. In the second case it is almost the same.