Vol 9, No 1 (2023): 25.05.2023

Full Issue

Articles

MODERN PROBLEMS OF AEROACOUSTICS OF PROPELLER-DRIVEN FIXED-WING AIRCRAFTS

Pogosyan M.A., Moshkov P.A.

Abstract

The modern classification of noise sources of propeller-driven fixed-wing aircraft is considered. Competitive community noise levels for single- and twin-engine for the projected light propeller-driven aircraft are formulated. An approach to community noise regulation of propeller-driven fixed-wing unmanned aerial vehicles is proposed. Modern approaches to assessing the community noise of propeller-driven fixed-wing aircraft are considered.

Journal of Dynamics and Vibroacoustics. 2023;9(1):6-15
pages 6-15 views

DESIGN DEVELOPMENT OF A HIGH-PRESSURE PNEUMATIC NOISE MUFFLER AND INVESTIGATION OF ITS EFFECTIVENESS

Zaika A.V., Igolkin A.A., Reshetov V.M., Safin A.I., Safina I.I.

Abstract

One of the main problems of pneumatic systems has been and remains an increased noise level, the side result of which is vibrations. Acoustic and mechanical processes negatively affect personnel, the environment and pipeline systems. Silencers of various designs are used to reduce the negative effects. The article presents an upgraded high-pressure pneumatic silencer, as well as the initial tests carried out. As a result, the acoustic efficiency of 41.2 dBS and 44 dBA was obtained.

Journal of Dynamics and Vibroacoustics. 2023;9(1):16-20
pages 16-20 views

SPECKLE INTERFEROMETRY APPLICATION FOR INVESTIGATING THE EFFECT OF PARAMETER MISTUNING OF TURBOMACHINE ROTOR WHEELS ON THEIR NATURAL VIBRATIONS

Zhuzhukin A.I., Nepein K.G.

Abstract

Compressor rotor wheel vibrations have been investigated using the digital speckle interferometry method. The diametrical mode case study experimentally revealed harmonic distortion of the distribution of the displacement along the circumference. Vibration mode distortion was also registered at one of wheel oscillation modes belonging to the family with the same circumference. It has been experimentally shown that parameter mistuning may not only result in changing the wheel disk vibration modes, but also in that of individual blade vibration modes, which makes the interpretation of rig test results more complicated. The localized modes were revealed at high frequencies of the wheel vibrations, when vibration amplitudes of one or several blades significantly exceed those of the rest.

Journal of Dynamics and Vibroacoustics. 2023;9(1):21-32
pages 21-32 views

APPLICATION OF THE RESONANCE METHOD AND THE SPECKLE INTERFEROMETRY METHOD FOR MEASURING THE DYNAMIC CHARACTERISTICS OF CONSTRUCTIONS

Osipov M.N., Sergeev R.N., Limov M.D.

Abstract

Experimental testing of rocket and space techniques is one of the most difficult, time-consuming and expensive stages of the development and creation of these products. Modern development methods tend to reduce the proportion of experimental studies and replace them with numerical modeling. However, the correspondence of the numerical model to the real object is determined by the initial data, so it is not possible to completely abandon the full-scale testing of products. Particular attention in the development and creation of rocket and space techniques is paid to vibration effects. Obtaining reliable basic dynamic characteristics of the product during vibration tests in a purely theoretical way is practically impossible. So the damping coefficients can only be determined experimentally. The paper analyzes the main methods for determining dynamic characteristics, and a choice is made in favor of the resonance method. The accuracy of determining the dynamic characteristics by the resonance method depends on the accuracy of the construction of the resonance curve. In this paper, to construct a resonance curve, it is proposed to use a speckle interferometer, which allows simultaneously recording the shape of natural vibrations and amplitude, using time averaging methods and speckle interferometry on a single speckle. It is shown that speckle interferometry on a single speckle makes it possible to measure the amplitudes of natural vibrations in real time and with high accuracyт ̵  less than one-eighth of the wavelength of the laser radiation used in the speckle interferometer. These circumstances are especially important in the development and creation of spacecraft with precision equipment.

Journal of Dynamics and Vibroacoustics. 2023;9(1):33-41
pages 33-41 views

DEVELOPMENT OF VIBRATION DAMPERS OF THE POWER FLUID TO REDUCE HYDRODYNAMIC NOISE IN PIPELINE SYSTEMS

Kryuchkov A.N., Ermilov M.A., Balyaba M.V., Ermilova E.N., Vidyaskina A.N.

Abstract

The article deals with the creation of dampers for pressure fluctuations of the working medium to solve the problem of reducing hydrodynamic noise in pipeline systems. It has been established that to solve this problem, it is possible to use reactive chamber vibration dampers provided that the condition of limiting the overall dimensions and the turbulent self-noise emitted by the narrow central channel is met. It is shown that meeting the requirements for a low self-noise level of such dampers leads to a significant increase in their overall dimensions, which is unacceptable for pipeline systems of on-board vehicles.

Journal of Dynamics and Vibroacoustics. 2023;9(1):42-49
pages 42-49 views

This website uses cookies

You consent to our cookies if you continue to use our website.

About Cookies