PSI - Issue 13

Marc Moonens et al. / Procedia Structural Integrity 13 (2018) 1708–1713

1713

6

M. Moonens et al. / Structural Integrity Procedia 00 (2018) 000–000 Table 2: Crack growth lives, in function of capillary internal pressure (all capillaries have a diameter of 2mm)

Without capillary

Capillary at 1.5 bar

Capillary at 2 bar

Capillary at 2.5 bar

Capillary at 3 bar

32800 cycles

31000 cycles

31000 cycles

31000 cycles

31000 cycles

which extent. To that purpose, simulations were run keeping the same geometry, but where the internal pressure inside the capillary was changed. Four di ff erent over-pressures have been tested (absolute pressure in the capillary is given): 1.5 bar, 2 bar, 2.5 bar and 3 bar. The crack growth lives, in function of the capillary internal pressures, are presented in table 2, while the crack growth curves are depicted in figure 5. From the results, it is clear that over-pressurization of the capillaries has strictly no e ff ect on the propagation. Indeed, the application of these low pressure loads on the capillary surface barely influence the stress field, thus implying no modification to the crack growth behavior.

4. Conclusion

The results of these numerical studies have shown that the introduction of small capillaries (0.5mm to 1mm di ameter) around the hole of a straight lug type component do not influence significantly the crack growth behavior of the component. Moreover, it has also been shown that over-pressurization of the capillaries up to pressures of 3 bar also do not a ff ect the crack growth behavior. This opens the door to possible applications of the eSHM system on actual components, as its e ff ectiveness in detecting fatigue cracks has been demonstrated previously, and as it has been shown here that it does not a ff ect the fatigue life of the monitored component

References

Boljanovic, S., Maksimovic, S., 2014. Fatigue Crack Growth Modeling of Attachement Lugs. International Journal of Fatigue 58, pp.66-74 De Baere, D., Strantza, M., Hinderdael, M., Devesse, W., Guillaume, P., 2014. E ff ective Structural Health Monitoring with Additive Manufacturing. 7 th European Workshop on Structural Health Monitoring, pp.2314-2321 Duflot, M., 2007. A Study of the Representation of Cracks with Level Sets. Int. J. Numer. Meth. Engng 70, pp.1261-1302 Esslinger, V., Kieselbach, R., Koller, R., Weisse, B., 2004. The Railway Accident of Eschede - Technical Background. Engineering Failure Analysis 11(2004), pp.515-535 Farrar, C.R., Worden, K., 2007. An Introduction to Structural Health Monitoring. Philos. Trans. R. A: Math. Phys. Eng. Sci. 2007 365, pp.303-315 Geuzaine, C., Remacle, J-F., 2009. Gmsh: a Three Dimensional Finite Element Mesh Generator with Built-in Pre- and Post-processing Facilities. International Journal for Numerical Methods in Engineering 79(11), pp.1309-1331 Hinderdael, M., Strantza, M., De Baere, D., Devesse, W., De Graeve, I., Terryn, T., Guillaume, P., 2017. Fatigue Performance of Ti-6Al-4V Additively Manufactured Specimens with Integrated Capillaries of an Embedded Structural Health Monitoring System. Materials 2017, 10, 993 Leuders, S., Thone, M., Riemer, A., Niendorf, T., Troster, T., Richard, H.A., Maier, H.J., 2013. On the Mechanical Behavior of Titanium Alloy TiAl6V4 Manufactured by Selective Laser Melting: Fatigue Resistance and Crack Growth Performance. International Journal of Fatigue 48, pp.300-307 Manson, S.S., Halford, G.R., 2006. Fatigue and Durability of Structural Materials. ASM International Moe¨s, N., Dolbow, J., Belytschko, T., 1999. A Finite Element Method for Crack Growth without Re-meshing. Int. J. Numer. Meth. Engng 46, pp.131-150 National Transportation Safety Board, 2007. In-flight Separation of Right Wing Flying Boat Inc. (Doing Business as Chalk’s Ocean Airways) Flight 101 Grumman Turbo Mallard (G-73T) N2969, Port of Miami, Florida, December 19, 2005. Accident report NTSB / AAR-07 / 04. Available from < https: // www.ntsb.gov / investigations / AccidentReports / Pages / AccidentReports.aspx > Reschetnik, W., Bruggemann, J.-P., Aydinoz, M.E., Grydin, O., Hoyer, K.-P., Kullmer, G., Richard, H.A., 2016. Fatigue Crack Growth Behavior of Additively Processed EN AW-7075 Aluminium Alloy. Procedia Structural Integrity 2 (2016), 3040-3048 Schijve, J., Hoeymakers, A.H.W., 1979. Fatigue Crack Growth in Lugs. Fatigue of Engineering Materials and Structures Vol. 1, pp. 185-201 Strantza, M., De Baere, D., Rombouts, M., Maes, G., Guillaume, P., Van Hemelrijck, D., 2015. Feasibility Study on Integrated Structural Health Monitoring Produced by Metal Three-Dimensional Printing. Structural Health Monitoring - An International Journal, Vol. 14, pp. 622-632 Wyart, E., 2007. Three-Dimensional Crack Analysis in Aeronautical Structures using the Substructured Finite Element / Extended Finite Element Method. Prom: Remacle, J-F., Pardoen, T.