SU1552035A1 - Method of determining damping characteristic of structure member - Google Patents

Abstract

The invention relates to the study of the vibration characteristics of complex objects and extends the field of application by determining the damping characteristic of an element of a non-separable structure made of a material with a frequency-independent damping characteristic. In the method for determining the damping characteristic of a structural element, by which the element 1 under investigation is isolated from other elements 2 connected to it, the harmonic oscillations of the element under investigation are excited at different frequencies at a constant amplitude of force or kinematic excitation, the resonant frequency and width are measured for each vibration mode resonance peak, which determine the damping characteristic of the element under study. The studied element 1 of the structure is isolated, rigidly fixed at the junction with other elements of the structure, the damping characteristics for each mode of vibration are compared, and the characteristic of the damping of the element under study is taken as the characteristic value that does not change with increasing vibration mode. The damping characteristic, which does not change with an increase in the oscillation mode, reliably characterizes the dissipative properties of the element under study, since The characteristics determined on each oscillation mode will differ only for those modes on which the oscillations will be transmitted through the connection of the element under study from a material with a frequency-independent damping characteristic with other elements of the structure. 1 il.

Description

31552035

The invention relates to the study of the vibration characteristics of complex objects, and in particular to methods

to to

the structure involved in the oscillation process will change as long as the vibrational energy

Characteristics of the damping-,. b. will be transmitted through the connection

no structural element.

The aim of the invention is to expand the field of application by determining the damping characteristic of an element of a non-separable structure from a material with a frequency-independent damping characteristic.

The drawing shows a diagram of the implementation of the method.

The method is carried out as follows: jpa.3QM.

The studied element 1 of the structure is insulated from other elements of the structure 2 connected to it, for which асс Assu is rigidly fixed to the junction 3. Using a vibrator (the arrow shows the direction of the action of the exciting force of the vibrator), excite the element 1 at different frequencies with a constant amplitude of force or kinematic excitation. Using a vibration sensor 4 reg. The amplitude-frequency characteristics of the investigated element 1 are reconstructed with the other elements of the 2 structure. Therefore, for structural elements of a material with a frequency-independent characteristic

JQ type of damping, stopping the change of the damping characteristic determined by the width of the resonance peak with increasing oscillation frequency means that the element under study

15 is vibration-insulated and definite non-variable with an increase in the oscillation mode, the damping characteristic characterizes the dissipative properties of the studied element

20 designs.

Claims (1)

The invention method for determining the characteristics damping the structural element, 25 according to which isolate the investigated structural element from the other structural elements connected with it, excite the harmonic oscillations of the element under study at various The oscillation pattern of the elemental frequencies under study at a constant amplitude of the sieve 1. For each vibration mode, find the resonant frequency and width of the resonance peak, from which the damping characteristic for each vibration mode is determined. The characteristic of the damping of the element under study 1 is taken to be its value, which does not change with increasing mode of oscillation. Hard fixing of the mass 3 at the junction of the investigated element 1 with other elements 2 of the structure provides the vibration isolation of the investigated element 1 when vibrations are excited at higher modes. With an increase in the frequency of oscillations, the coefficient of transfer of vibrational energy through the boundary of the element under study with a mass rigidly fixed on it will decrease and the recorded damping characteristic characterizing the energy dissipation of the part 35 40 45 50 For each mode of oscillation, the resonant frequency and width of the resonance peak are measured, which determine the damping characteristic of the element under study, which differs by expanding the field of application by defining the damping characteristic of the element of a nonseparable structure made of material with frequency-independent damping characteristic, the insulation of the investigated structural element is produced by rigidly fixing the mass at the junction of the investigated The obtained damping characteristics for each vibration mode are compared with other structural elements, and the damping characteristic of the element under study is taken to be its value, which does not change as the vibration mode increases. the investigated element 1 with other elements 2 designs. Therefore, for structural elements of a material with a frequency-independent damping characteristic, the cessation of a change in the damping characteristic determined by the width of the resonant peak with increasing oscillation frequency means that the element under study vibroisolated and determined unchanged with increasing mode of oscillation; damping characteristic characterizes the dissipative properties of the studied element designs. The invention method for determining the characteristics damping the structural element, by which they isolate the investigated structural element from other structural elements connected with it, excite the harmonic oscillations of the element being investigated at various frequencies at constant amplitude For each mode of oscillation, the resonant frequency and width of the resonance peak are measured, which determine the damping characteristic of the element under study, which differs by expanding the field of application by defining the damping characteristic of the element of a nonseparable structure made of material with frequency-independent damping characteristic, the insulation of the investigated structural element is produced by rigidly fixing the mass at the junction of the investigated The obtained damping characteristics for each vibration mode are compared with other structural elements, and the damping characteristic of the element under study is taken to be its value, which does not change as the vibration mode increases.