Assessment of a Complex Aerospace Design through Optical Techniques

Abstract:

This paper reports the design assessment carried out on a subassembly of an advanced rocket using experimental techniques. The design was very complex and critical, since a cylindrical shell had a square cutout on the axial-hoop plane interacting with a notch in the axial-radial plane. Herein, two optical techniques have been employed for assessing the interaction between the notch and the cutout, and their individual contributions to the strain-field. Initially, a photoelastic model was studied to estimate the stresses at the notch tip. Subsequently, DIC was employed for measuring strains at the notch during the ground based testing of the actual component. The outcomes of these two experiments showed that the effect of the cutout to the strain concentration was negligible due to the extra stiffness provided by other assemblies.

• Periodical: Applied Mechanics and Materials (Volumes 592-594)
• Pages: 1006-1010
• DOI: https://doi.org/10.4028/www.scientific.net/AMM.592-594.1006
• Online since: July 2014
• Authors: Digendranath Swain*, Jeby Philip, S. Annamala Pillai
• Keywords: Cut-Out, Digital Image Correlation (DIC), Notch, Optical Techniques, Photoelasticity, Strain Concentration, Stress Concentration

References

[1] J. W. Dally, W. F. Riley, Experimental Stress Analysis, second ed., McGraw-Hill Book Company, USA, (1965).

[2] K. Ramesh, Digital Photoelasticity, first ed., Springer-Verlag Berlin, (2000).

[3] M. A. Sutton, J. Orteu, H. W. Schreier, Image Correlation for Shape, Motion and Deformation Measurement: Basic Concepts, Theory and Applications, Springer New York, (2009).

DOI: 10.1007/978-0-387-78747-3

[4] VIC-3D and VIC-SNAP supplied by Correlated Solutions, Inc., USA.

[5] D Swain, J Philip, S A Pillai, Optimized Digital Image Correlation (DIC) for measuring high strain gradient regions, Indian Conference on Applied Mechanics (INCAM), IIT Madras, July (2013).