Labyrinth seals are commonly used in turbomachinery in order to control leakage flows. Flutter is one of the most dangerous potential issues for them, leading to High Cycle Fatigue (HCF) life considerations or even mechanical failure. This phenomenon depends on the interaction between aerodynamics and structural dynamics; mainly due to the very high uncertainties regarding the details of the fluid flow through the component, it is very hard to predict accurately. In 2014, as part of the E-Break research project funded by the European Union (EU), an experimental campaign regarding the flutter behaviour of labyrinth seals was conducted at Centro de Tecnologias Aeronauticas (CTA). During this campaign, three realistic seals were tested at different rotational speeds, and the pressure ratio where the flutter onset appeared was determined. The test was reproduced using a linearized uncoupled structural-fluid methodology of analysis based on Computational Fluid Dynamics (CFD) simulations, with results only in moderate agreement with experimental data. A procedure to adjust the CFD simulations to the steady flow measurements was developed. Once this method was applied, the matching between flutter predictions and the measured data improved, but still some discrepancies could be found. Finally, a set of simulations to retain the influence of the external cavities was run, what further improved the agreement with testing data.

More than 5% of the global population suffers from disabling hearing loss, primarily sensorineural hearing loss (SNHL). SNHL is often caused by factors such as vascular disorders, viral infections, ototoxic drugs, systemic inflammation, age-related labyrinthine membrane degeneration, and noise-induced hearing loss (NIHL). NIHL, in particular, leads to changes in blood-labyrinth-barrier (BLB) physiology, increased permeability, and various cardiovascular health issues, including hypertension, diabetes, neurological disorders, and adverse reproductive outcomes: Research has connected an elevated risk of hypertension with loud noise. The endocrine and autonomic nervous systems are also linked to arousal following an acute exposure to loud sounds. As a preventive option for both NIHL and hypertension as sequela of noise trauma, we present the transcutaneous vagus nerve stimulation (taVNS). taVNS may be appropriate to prevent NIHL-associated hypertension, as it typically reduces blood pressure and improves heart rate variability. On the other hand, normalizing cerebral blood flow preserves cochlear homeostasis, which is maintained by the BLB.The paper provides a comprehensive overview of NIHL pathophysiology and the impact of noise on auditory structures and function. Our research focuses on the auditory structures and functions affected by noise, such as the strial BLB, as well as the autonomic changes caused by NIHL, specifically the emergence of NIHL-associated hypertension as a primary comorbidity. We describe the clear link between taVNS use and increased HRV and slower progression of chronic hypertension, and we propose it as a cutting-edge preventive option for both conditions.