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This paper shows and discusses the use of the finite element software ANSYS for simulation of the behavior of sound waves in a ducts-plenum system. The modeling is intended for didactic purposes, beginning with simple three-dimensional geometries of ducts and plenum. Two conditions can be included: (1) with and without acoustical absorbent materials on the inside walls of the ducts and (2) including or not labyrinths. The analysis allows students to see the behavior of the waves inside the duct-plenum system and they can manipulate the parameters of the model to improve the attenuation characteristics of the system.

In this paper the finite elements method is used to simulate the transient behavior of impact machinery and its foundation. Using the software package ansys, two cases are modeled: first, the impact machine directly mounted on the floor, and second, the machine mounted over an inertia block foundation. The results of the modeling permit clear visualization of transient vibrations in the machine and how they are transmitted to the foundation and the floor. How to use this modeling for didactic purposes is discussed.

Damage in single lap joints under shear load was assessed. Specimens were tested in accordance with ASTM D1002-10(2019). Controls were taken on adhesive and surface preparation, adhesive thickness, and load-specimen alignment. Digital Image Correlation was used to measure stresses over the adhesive, and shear modulus variation and percent of damage were assessed. Results show shear modulus losses against shear stress. Finally, early damage evolution was determined up to 10% of the shear load rate and later, increasing up to 70%-96%.