Search results for "aerodynamic"
showing 6 items of 66 documents
Acoustic, myoelectric, and aerodynamic parameters of euphonic and dysphonic voices: a systematic review of clinical studies
2021
Background: At present, there is no clinical consensus on the concept of normal and dysphonic voices. For many years, the establishment of a consensus on the terminology related to normal and pathological voices has been studied, in order to facilitate the communication between professionals in the field of the voice. Aim: systematically review the literature to compare and learn more precisely the measurable and objective characteristics of the acoustic, aerodynamic and surface electromyographic parameters of the normal and dysphonic voices. Methods: The PRISMA 2020 methodology was used as a review protocol together with the PICO procedure to answer the research question through six databa…
Validity of a novel device for indoor analysis of cyclists' drag area
2021
Cyclists need to measure aerodynamic resistance accurately and reliably, as well as economically. Devices such as Notio Aerostick, an equipment device that includes one pitot tube, have appeared for this purpose. The aim of this study is, therefore, to test the reliability and degree of agreement in the evaluation of the CdA (coefficient of aerodynamic drag), assessed by means of the Notio Aerostick compared to the Virtual Elevation (VE) and Martin mathematical models.Seventeen professional cyclists rode in a 250-metre-long velodrome covered with a concrete surface with their own time trial bikes. Each cyclist completed three rides of 15 laps at constant speed for the evaluation of the CdA,…
Previsione delle prestazioni del veicolo su strada: stato dell’arte
2016
Questo lavoro contiene una rassegna dei metodi che sono usati per la previsione delle prestazioni del veicolo su strada, in dipendenza del motore installato. La prima parte mostra il calcolo delle resistenze al moto, cioè le forze che il veicolo deve vincere per avanzare sulle strade piane e in salita. Particolarmente interessante appare la parte che riguarda la resistenza aerodinamica, della quale si tratta di metodi sperimentali (galleria del vento), metodi empirici e metodi CFD. Si propone inoltre l’applicazione della norma CUNA sulla velocità per la determinazione dei consumi anche al calcolo dei coefficienti aerodinamici. La rassegna esclude la resistenza accidentale in curva perché no…
Aerosolization Performance of Jet Nebulizers and Biopharmaceutical Aspects
2019
In this work, 13 jet nebulizers, some of which in different configurations, were investigated in order to identify the biopharmaceutical constraints related to the quality attributes of the medicinal products, which affect their safety, efficiency, compliance, and effectiveness. The aerosolization parameters, including the aerosol output, aerosol output rate, mass median aerodynamic diameter, and fine particle fraction, were determined according to the European Standard EN 13544-1, using sodium fluoride as a reference formulation. A comparison between the aerosol output nebulization time and the fine particle fraction displayed a correlation between the aerosol quality and the nebulization …
Improving the Downwind Sail Design Process by Means of a Novel FSI Approach
2021
The process of designing a sail can be a challenging task because of the difficulties in predicting the real aerodynamic performance. This is especially true in the case of downwind sails, where the evaluation of the real shapes and aerodynamic forces can be very complex because of turbulent and detached flows and the high-deformable behavior of structures. Of course, numerical methods are very useful and reliable tools to investigate sail performances, and their use, also as a result of the exponential growth of computational resources at a very low cost, is spreading more and more, even in not highly competitive fields. This paper presents a new methodology to support sail designers in ev…
Ski jumping takeoff in a wind tunnel with skis.
2011
The effect of skis on the force–time characteristics of the simulated ski jumping takeoff was examined in a wind tunnel. Takeoff forces were recorded with a force plate installed under the tunnel floor. Signals from the front and rear parts of the force plate were collected separately to examine the anteroposterior balance of the jumpers during the takeoff. Two ski jumpers performed simulated takeoffs, first without skis in nonwind conditions and in various wind conditions. Thereafter, the same experiments were repeated with skis. The jumpers were able to perform very natural takeoff actions (similar to the actual takeoff) with skis in wind tunnel. According to the subjective feeling of the…