The calculation of discharge currents in a torus with a continuous conducting liner

A continuous metallic liner has been introduced into the Zeta torus. The parasitic current flowing in this liner will limit the permissible rate of current increase in the discharge. Therefore the behaviour of the system when gas and liner currents are of the same order must be calculated, and for this purpose an equivalent circuit is established. In a first analysis, all the elements in this circuit are assumed to be constant throughout the discharge, and the currents flowing are found by normal interpretation of the appropriate thirdorder differential equations. These results are useful for machine trials, and provide a check on the second stage of analysis in which the variation of the inductance of the gas during the pulse is taken into account. This second calculation is of course much more difficult than the first, and is performed with a digital computer. The computer has now examined the conditions which are of immediate interest, and has shown that in all of them the energy loss in the liner can be tolerated. Sufficient data are now available for deduction of the discharge parameters to be made from experimental results.