PSI - Issue 24

Filippo Cianetti et al. / Procedia Structural Integrity 24 (2019) 526–540 Author name / Structural Integrity Procedia 00 (2019) 000–000

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4. Conlclusions

Simulating a qualification test is a valid mitigation of the risk that a component may not survive the actual tests, with strong impacts in terms of costs and time. The reliability of the simulation therefore represents the target to be pursued, right from the prototype phase, carefully validating each step: from the FEM model, to loads, passing through the material and the dynamic response. A calculation procedure that respects these canons must also be industrially serviceable, or able to manage computationally burdensome models in a reasonable time. This demarcated the line followed by the authors in this work where a durability test is punctually examined, identifying the critical aspects and proposing solution strategies. Extremely simple experimental tests were used, optimizing the size of the expensive database, forcing the model ”a priori” and drawing the maximum gain with simple, easily implementable and reproducible tools. In an e ff ort to meet real needs, the frequency domain has never been abandoned, demonstrating its applicability, and benefiting from the substantial reduction in calculation times Braccesi et al. (2017). To this end, the sine on random test has been converted in terms of PSD, once again providing an empirical feedback on what has been done. In this transversal domain, which ranges from signal theory, to dynamics, to FEM, procedures like this proposed by the authors, represent the clear demonstration of how complex problems require a multidisciplinary approach. If on the one hand the work wants to o ff er a streamlined and e ff ective operational procedure to the simulation of the qualification test, on the other it intends to act as a starting point for positive and constructive criticism. One wonders whether, on the basis of a constant experimental validation Atamturktur et al. (2015); Xu et al. (2012) a simulation can take on the character of evidence in front of the certifier, in a critical area such as aeronautics.

Acknowledgements

The author would like to thank the Technical O ffi ce of Maintenance Army Center of Light Armament (Terni, Italy), especially Maj. Eng. Giuseppe Polara, Maj. Eng. Ettore Lucci and Mr. Daniele Conti for the intellectual, technical and practical support to experimental activities.

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