Additively-Manufactured Stainless Steel Wind Tunnel Model Support Featuring Honeycomb Structures for Vibration Attenuation

Abstract

Wind tunnel model support ( WTMS) is an indispensable component of wind tunnel testing. However, the vibrations in the model-support system can compromise data accuracy and pose significant safety risks. Therefore, it is crucial to mitigate vibration of WTMS. In this study, we proposed an approach for vibration attenuation by incorporate honeycomb structures into the design of the WTMS. To this end, stainless steel WTMSs with integrated honeycomb structures were fabricated by selective laser melting (SLM). Phase composition, microstructure, and mechanical properties of the SLMed stainless steel were studied. Results showed that stainless steels prepared under optimized SLM processing parameters exhibited high crystallinity and consisted of single-phase Fe-Cr-Ni alloy with face-centered cubic structure. Additionally, minor alloying elements were uniformly distributed throughout the material. The stainless steels showed robust mechanical properties, including tensile strength of approx. 1 GPa, elongation of approx. 8%, compressive strength of approx. 1.4 GPa. These robust mechanical properties can be attributed to the formation of a cellular structure and a large number of tangled dislocations. Furthermore, vibration responses of the WTMS with dense and honeycomb structures were comparably investigated in a wind tunnel. It was found that incorporating honeycomb structures effectively mitigated both the first-order and the third-order resonant response. The vibration reduction mechanism can be attributed to the occurrence of local resonance when the natural frequency of the internal periodic unit of the WTMS closely matched the vibration frequency of the model. The utilization of honeycomb structures holds significant potential for achieving vibration attenuation in WTMS.

Keywords: Additive Manufacturing, wind tunnel, stainless steel, hierarchical structure, vibration attention.