Benchingmark and implementation of a generalized MITL flow model

Abstract

A generalized magnetically insulated transmission line (MITL) flow model has been developed to treat dynamic MITL problems [1]. By including electron pressure in the model and allowing non-zero values of the electric field at the cathode, this MITL model can treat both emission and re-trapping of flow electrons. Most previous MITL flow models only describe equilibrium flow conditions without emission or re-trapping and cannot adequately treat dynamic situations. Such dynamic situations are common and include impedance transitions along the line, variable impedance transmission lines, coupling to loads, etc., all of which can cause electron emission from the cathode and/or electron re-trapping onto the cathode. The model is being benchmarked against particle-in-cell (PIC) simulations using the LSP code [2]. Of particular interest for this benchmarking effort is the treatment of re-trapping waves that occur when the MITL is terminated by an under-matched load. Ultimately, the model will be incorporated into a transmission line code such a BERTHA [3] so that MITL problems can be studied more quickly and efficiently than with PIC codes.