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PurposeThis paper aims to assess the feasibility of additively manufactured wind tunnel models. The additively manufactured model was used to validate a computational framework allowing the evaluation of the performance of five wing models. Design/methodology/approachAn optimized fighter wing was additively manufactured and tested in a low-speed wind tunnel to obtain the aerodynamic coefficients and deflections at different speeds and angles of attack. The flexible wing model with optimized curvilinear spars and ribs was used to validate a finite element framework that was used to study the aeroelastic performance of five wing models. As a computationally efficient optimization method, homogenization-based topology optimization was used to generate four different lattice internal structures for the wing in this study. The efficiency of the spline-based optimization used for the spar-rib model and the lattice-based optimization used for the other four wings were compared. FindingsThe aerodynamic loads and displacements obtained experimentally and computationally were in good agreement, proving that additive manufacture can be used to create complex accurate models. The study also shows the efficiency of the homogenization-based topology optimization framework in generating designs with superior stiffness. Originality/valueTo the best of the authors’ knowledge, this is the first time a wing model with curvilinear spars and ribs was additively manufactured as a single piece and tested in a wind tunnel. This research also demonstrates the efficiency of homogenization-based topology optimization in generating enhanced models of different complexity.
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This content will become publicly available on December 5, 2025
Sintering model for predicting distortion of additively manufactured complex parts
PurposeThis study aims to provide understanding of the influence of external factors, such as gravity, during sintering of three dimensional (3D)-printed parts in which the initial relative density and cohesion between the powder particles are lower compared with those present in the green parts produced by traditional powder technologies. A developed model is used to predict shrinkage and shape distortion of 3D-printed powder components at high sintering temperatures. Design/methodology/approachThree cylindrical shape connector geometries are designed, including horizontal and vertical tubes of different sizes. Several samples are manufactured by binder jetting to validate the model, and numerical results are compared with the measurements of the sintered shape. FindingsSimulations are consistent with empirical data, proving that the continuum theory of sintering can effectively predict sintering deformation in additively manufactured products. Originality/valueThis work includes the assessment of the accuracy and limits of a multiphysics continuum mechanics–based sintering model in predicting gravity-induced distortions in complex-shaped additively manufactured components.
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- Award ID(s):
- 2119832
- PAR ID:
- 10636046
- Publisher / Repository:
- Emerald Publishing Limited
- Date Published:
- Journal Name:
- Rapid Prototyping Journal
- Volume:
- 30
- Issue:
- 11
- ISSN:
- 1355-2546
- Page Range / eLocation ID:
- 369 to 383
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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