Shock analysis of an antenna structure subjected to underwater explosions

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2015

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Demir, Mehmet Emre

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Antenna structures constitute main parts of electronic warfare systems. Mechanical design is as crucial as electromagnetic design of antenna structures for proper functioning and meeting high system performance needs. Failure of mechanical and electronic structures operating under shock loading is a common occurrence in naval electronic warfare applications. A complete shock analysis of the dipole antenna structure subjected to underwater explosions is performed to foresee adverse effects of mechanical shock phenomena on the antenna structure. Theoretical models of the antenna structure; namely mathematical model and finite element model, are built on multi-degree-of-freedom approach. Modal properties are derived from Classical Beam Theory and transient responses are obtained by Recursive Filtering Relationship(RFR) Method for the mathematical model. Input shock loading is synthesized from assessed shock specification to classical shock input. Finite element analysis of the analytical model is performed on ANSYS® platform. Comparisons of analytical results are presented for interchangeable use of proposed models. Numerical results are verified with both modal and transient results collected from experimental analysis. Experimental analysis is performed for exact dimensions of antenna structure subjected to synthesized shock input criteria. Shock severity for antenna structure is presented for both electrical and mechanical components. Design roadmap is drawn within the limitations set for proper antenna functioning with desired performance. Shock isolation theory is also explained and applied to the antenna structure in order to obtain shock responses below limitations mentioned. Thus, the complete shock analysis of the antenna structure is performed for antenna design to withstand underwater shock explosions.

Subject Keywords

Shock waves., Antennas, Dipole., Antennas (Electronics)., Electronics in military engineering.

URI

http://etd.lib.metu.edu.tr/upload/12619172/index.pdf
https://hdl.handle.net/11511/24904

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Graduate School of Natural and Applied Sciences, Thesis

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Citation Formats

M. E. Demir, “Shock analysis of an antenna structure subjected to underwater explosions,” M.S. - Master of Science, Middle East Technical University, 2015.