SU169819A1 - Method for determining attenuation coefficient of oscillatory processes - Google Patents

Description

There is a known method for measuring the attenuation coefficient of a sound with respect to the amplitude of the probe pulses, measured with a lag meter and a certain length of the measurement base.

The peculiarity of the proposed method is that in its implementation the attenuation 1p1, oscillatory process, applied as a voltage, is divided into positive and negative pulses on a symmetric diode and the attenuation coefficient is determined from the integral values of these pulses. This difference improves the accuracy and stability of measurements.

With this method, it is possible to calibrate the scale of the lagometer directly in units of decrement, regardless of the oscillation period, as well as the repetition period and the amplitude of the damping process.

The damped oscillatory process is described by the equation

. 2-,

L Sin - t.

If we specify the repetition process period T, provided that Ti 3 -fТ is at, where, then the mean value of A for positive half-periods A + can be recorded with sufficient accuracy as follows:

/,about

1 g

2t:

A-L - Sow Sow at tdt:

  J

-

  sin y r dt

g .c "i .1

 P T

2p T

AO

+ e (14-6-5-g

t S2 471

pt-y

+ e-25-f .... | g-m5)

25

wherein

lornjiio for negative poluperiomozhpo write:

2 (1 +

4g ;:

7 y

. -} - e-)

And the values of A +

;.- puppy aosilutnyh

lovatelyu, 6 2 1p- A

PREEL, METH of invention

The method for determining the attenuation coefficient of oscillatory processes by measuring the amplitude of oscillations using a correlation meter, and an impregnator of a lagometer, calibrated in units of a damping factor, characterized in that

increasing the accuracy and stability of measurements, damping the oscillations; 1, pulsed, supplied as a voltage, is divided into positive and negative pulses on a balanced diode and the attenuation coefficient is determined relative to the integral damping of these pulses.