Karachun V.V., Mel’nick V.N.
National Technical University of Ukraine “KPI”
DEVICE FOR TESTING DEVICES ON
MULTICOMPONENT VIBRATION ON SINGLE-COMPONENT VIBROEXCITER
Acoustic load of elements of aircraft constructions in
terms of their exploitation use, as is known, has a spatial character. It is no
difficulties to reproduce this field for levels below 130 dB, for example with
help of the system of loudspeakers. At the same time, a field of 150 ... 180 dB
in a very wide range of frequencies becomes a very complicated technical
problem, that need on the one hand, a powerful generator of sound, on the other
- special stands and equipment for supplying their functioning while the
simultaneous solution environmental problems associated with their high energy.
In this context occurs the question regarding
equivalent replacement while studying the external acoustic excitation with
another, more simply realizable. Further, comparing the test results it would
be sufficient to determine the degree of similarity between these factors by
their influence on test objects. Of course, it is not possible to to name a
replacement equivalent, but in first approximation, it will allow to make a
regulatory evaluation of the values to passport.
Because the fact that while acoustic load in
mechanical systems generates vibrations (acoustic vibration), then naturally,
there is an idea about physical modeling of not sound field but vibration field
as easier to realize, and to elect as generator serially produced vibration
generator. Unfortunately, uniaxial exciters, which found application in
practice of testing and regulatory works, cannot play a multicomponent spatial
vibration without additional complex technical solutions. The device that can
solve a number of issues is free of these defects.
The invention relates to test systems, namely to devices for testing
products on multicomponent vibration on single-component vibroexciter. Purpose
is expansion of functionality through the simultaneous test of one class
products on two- and tri-component vibrations. The device has a plate 1 which
is fixed on the table of single-component vibroexciter and connected to plate 1
working plates which has inclined to the plane of plate 1 surfaces formed by
rectangular plates 2 on which the trial products are installed for the
two-component vibration, and triangular prisms 5 on which the trial products
are installed for the tri-component vibration. Plates 2 are connected with one
by equal sides 3 with plate 1, and other sides 4 - between themselves. Each
triangular prism 5 is connected by lateral faces 6 with one of the plates 2,
the lateral faces 6 of prism 6 are parallel to the free sides 7 of plates 2
(fig. 1).
The device works as following. Plate 1 is fixed on the table of
vibroexciter. On rectangular plates 2 are placed from one to several products
that will be subject to two- component vibration. For tri-component vibration,
studied products should be placed on the lateral sides 6 of triangle prisms 5.
If the test on single-component vibration is necessary products are attached on
table 1.
Vector 
of vibration
acceleration on rectangular plates 2 decomposes into two components on the
orthogonal axes 
and 
according
to the components 
and 
. Modules of vectors can be defined by choosing
the angle 
of
rectangular plate 2 to plate 1, and 
. For plate 2 is reasonable the ratio
.
Vector 
of vibration
acceleration on the lateral face 6 of triangular prisms 5 due to its pitch to
plate 1 to an angle 
(
) is decomposed according to 
, 
and 
, and while there are the following ratio:
;
;
Creating identical kinematics-time terms for testing products of one
class at simultaneous action by a single, two- and tri-component vibrations
enhances functionality of device.
Appearance is shown in fig. 2.
