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Student Number : 9608998A - MSc dissertation - School of Electrical and Information Engineering - Faculty of Engineering and the Built Environment / The history of flux compression is relatively short. One of the founders, a Russian physicist, Sakharov developed the idea of compressing a magnetic field to generate high magnetic fields and from this he also developed a generator to produce current impulses. Most of this initial work was performed in military research laboratories. The first open source literature became available in the 1960s and from there it has become an international research arena. There are two types of flux compression generators, field generators and current generators. These are discussed along with the basic theory of flux compression generators and related physics. The efficiency of generators is often quite low. However in many generators high explosives are used and because of their high energy density, the current or field strength produced is substantially greater then the initial source. This of course limits the locations possible for experimental work and subsequently limits the industrial applications of flux compression generators . This research presents a theoretical design for a non-explosive flux compression generator. The generator is designed to produce a current impulse for tests in laboratory and remote locations. The generator has the advantage of being non-destructive, therefore reducing costs, and allowing for repeatable experiments. The design also reduces the possibilities or many of the loss mechanisms.

Lightning current with high amplitude disseminates through the body of aircraft and causes physical damages including the delamination and puncture of materials. Also , such high-amplitude and high-frequency current could interfere with electronic devices through electromagnetic coupling with the conductive interfaces of an airplane. Hence, robust protection against lighting strike is essential in the aerospace industry. Carbon Fiber Reinforced Polymer (CFRP) Matrix Composites have become significant alternatives to conventional metal-base materials. Despite the superior physical and structural properties of CFRP composites, these materials are vulnerable to lightning strikes due to the low electrical conductivity compared to the metal counterpart. Many researchers have been working on the lightning strike damage mitigation of CFRP composites by increasing the electrical conductivity of materials. Conventional methods are adding conductive layers such as metal foil and copper mesh to the composite structures. These layers are added to the composite structure during the manufacturing process and are placed at the top layer for the effective bypassing of lightning current to the ground. While adding the conductive layers reduces the lightning strike damage significantly, the industry is more interested in using conductive nanofillers to prevent the corrosion of metal layers in contact with carbon fibers and to avoid the higher weight of conductive layers than nanofillers. The lightning damage mitigation methods are studied by applying lightning strike current to the CFRP composites using an impulse current generator. Conventional lightning strike damage tolerance of CFRP composites are prone to misinterpretation. The risk of misinterpretation originates from the lack of standards clearly defining testbed design requirements including electrode size and ground electrode edge configuration. In this dissertation, the effects of testbed configuration including discharge and ground electrode on lightning strike damage evaluation studies are demonstrated. Finite element analysis is applied to perform the simulations through the COMSOL Multiphysics to validate the experimental test results. Furthermore, after improving the testbed design, carbon black was added to the CFRP composites as a cost-effective additive for lightning strike damage mitigation performance. Correlations between lightning strike damage intensity and the added carbon black fillers as well as with other additive nanofillers are reported.