Links table
Abstract and 1 introduction
2 cell design unit and analysis
3 experimental descriptions and cell cell
4 AM Labyrinthine
4.1 The design and manufacture of the painting
4.2 FE model AM
4.3 AM Description of the board
4.4 AM The results of the painting of the painting
5 numerical evaluation of the various solutions of the maze’s sound absorption board
5.1 MacROCell with support cavity
5.2 Results
Conclusions, estimates and references
The first appendix
5.1 MacROCell with support cavity
Given the promising results of the design described in the previous sections, and the good agreement between numerical and experimental results, another digital study is conducted to assess possible developments in the AM of AM Voice absorption panel. The goal is to assess its audio performance under various design compositions. More specifically, three additional configurations are evaluated: a) adding melanamine foam inside UCS to the painting; B) Add the steel rear support cavity applied in correspondence with the non -equal surface of the plate (in this case with open openings), with/without filling melamine foam; C) Mix a) + b). The audio performance of each of these features can be studied and compared to the original composition (which is considered as a foundation), which again leads to a FE simulation with Comsol Multiphysics, with a focus on one marcocell, is considered a representative of the plate behavior. Again, thermal effects should be calculated.
In the second composition, the AM board is associated with an additional audio field of a depth equal to four times its side length (Figure 11 A and B). The conditions of the unimaginable layer limits (PML) is applied to the back of the audio field. Again, the structural fields are completely solid, because the results of simple and simple audio simulation lead to minimal differences. The foam is chosen as melanin, whose properties are summarized in Table 1.
5.2 Results
Figure 12 shows the absorption coefficient calculated in the three studied cases. The foundation line, the corresponding to the intermittent curve in the 10b Figure, appears in red. The effect of the presence of a supportive (thick 5 mm) support is filled with melanamine foam in Figure 11) is the conversion of absorption peaks to low frequencies (below from 1 kg to about 700 Hz), with a beneficial effect of low frequencies. On the other hand, adding foam filling in AM cavities leads to a more consistent absorption coefficient over the entire frequency, at the expense of a lower efficiency in AM work frequencies. However, this solution can be useful in the case in which a more distributed sins effect on the entire frequency is required, not in specific targeted frequencies. Other types of foams can also be seen to improve the common effect with AM.
Authors:
(1) F. nistri, Department of Applied Science and Technology, Politecnico Di Torino, Turin, Italy, Politecnico Di Milano, Milan, Italy;
(2) VH Kamrul, Politecnico Di Milano, Milan, Italy;
(3) L. Bettini, politecnico di Milano, Milan, Italy;
(4) E. Musso, Politecnico Di Milano, Milan, Italy;
(5) D. Piciucco, politecnico di Milano, Milan, Italy;
(6) M. Zamello, Politecnico Di Milano, Milan, Italy;
(7) In its capacity Gliozzi, Department of Applied Science and Technology, Politecnico di Torino, Turin, Italy;
(8) Ao Krushynska, College of Science and Engineering, University of Gronengen, Grungen, Netherlands;
(9) NM PUGNO, Biomedical Laboratory, Bionic, Nano, Meta Mateials & Mechanic, University of Tinto, Trento, Italy, College of Engineering and Materials Science, Queen Mary University in London, UK;
(10) L. Sangiuliano, SRL, Milan, Italy;
(11) L. Shtrepi, “Galileo Ferraris”, Politecnico Di Torino, Turin, Italy;
(12) F. Bosia, Department of Applied Science and Technology, Politecnico Di Torino, Turin, Italy and author against ([email protected]).
