Finite element analysis applied to open-end spinning noise.
Noise-Con 81, Proceedings of the 1981 National Conference on Noise Control Engineering, June 8-10, 1981, Raleigh, North Carolina. Royster LH, Hart FD, Stewart ND, eds., Poughkeepsie, NY: Noise Control Foundation, 1981 Jun; :195-198
The rotation of the beater and rotor of an open end spinning machine was simulated using finite element analysis, with the objective of comparing the results to noise spectra of the machine and identifying sources of noise. The overall sound pressure level, measured 1.5 meters from the floor and 1 meter from the center of a machine having 24 spinning units, was 90 decibels (dB). The bowing, or whirl, of a rotating shaft was predicted by modeling the shaft as a Bernoulli Euler beam and treating the critical rotational speed as natural frequencies of the beam in transverse bending. Beam elements or solid pipe elements were used in the finite element simulations of the rotor and beater, which were discretized into 39 and 15 elements, respectively. The eigenvalues and thus the critical speeds of the beater and rotor were determined by a finite element computer program. Shaft speeds were also determined using a transfer matrix program, which replaced each shaft with lumped masses connected by massless shaft sections. In addition, vibrational frequencies generated by surface defects in the ball bearings were calculated. Seven of the peaks in the noise spectrum were identified with specific defects in the beater or rotor. The authors conclude that a reasonable level of understanding of noise and vibrational characteristics of open end spinning machines can be attained through a combination of classical bearing theory, finite element computer modeling, and transfer matrices, combined with narrow band spectral analysis.
NIOSH-Grant; Textiles-industry; Computer-models; Industrial-noise; Acoustical-measurements; Noise-analysis; Acoustics; Noise-sources; Analytical-models
Royster-LH; Hart-FD; Stewart-ND
Noise-Con 81, Proceedings of the 1981 National Conference on Noise Control Engineering, June 8-10, 1981, Raleigh, North Carolina