Accession Number : ADA190576

Title :   Experimental Comparison of Lightning Simulation Techniques to CV-580 Airborne Lightning Strike Measurements.

Descriptive Note : Master's thesis,

Corporate Author : AIR FORCE INST OF TECH WRIGHT-PATTERSON AFB OH SCHOOL OF ENGINEERING

Personal Author(s) : Braza, Rudy M

PDF Url : ADA190576

Report Date : Dec 1987

Pagination or Media Count : 132

Abstract : Experimental tests on the Lightning Test Cylinder, which further investigated the assessment of lightning simulation techniques conducted by Butters et al., included swept frequency continuous wave (SFCW), current pulse, and shock-excitation. Designed to model the fuselage of an aircraft, the aluminum test cylinder is over ten meters long with a one meter diameter. To test the effects of various aircraft construction materials, the cylinder was constructed with an aperture where various composite and metal panels can be mounted. The research involved determination of the electrical field and magnetic field response transfer functions for each simulation test technique. With these transfer functions, analysis and comparison of the external and internal field responses between the SFCW, current pulse, and shock-excitation tests were made. A major portion of the research was to examine the validity of the linear model for the current pulse simulation technique. In this investigation, transfer functions were derived for various current pulse waveforms. The current waveforms injected into the test cylinder included a 20 kA unipolar, double-exponential pulse and two oscillatory waveforms with peak amplitudes of 20 kA and 100 kA. The research effort also involved investigation of the induced E-dot (dE/dt) and V-dot (dV/dt) transients of the shock-excitation simulation test for various composite structures. The results of this experimental effort on the Lightning Test Cylinder were then correlated to CV-580 airborne lightning measurements. Differences and similarities between the measured results are presented.

Descriptors :   *LIGHTNING, AIRCRAFT, ALUMINUM, AMPLITUDE, COMPARISON, COMPOSITE STRUCTURES, CONSTRUCTION MATERIALS, CONTINUOUS WAVES, CYLINDRICAL BODIES, DIAMETERS, ELECTRIC FIELDS, EXCITATION, EXPERIMENTAL DESIGN, EXTERNAL, FUSELAGES, INTERNAL, LINEAR SYSTEMS, MATHEMATICAL MODELS, METALS, METHODOLOGY, OSCILLATION, PANELS, PEAK VALUES, PULSES, RESPONSE, SHOCK TESTS, SIMULATION, SWEEP FREQUENCY TECHNIQUES, TEST METHODS, TRANSFER FUNCTIONS, WAVEFORMS, THESES

Subject Categories : Atmospheric Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE