Experimental investigations of acoustic field in sea shelf zone

Developed experimental facility allows one to generate acoustic pressure within the intervals from 105 to 106 Pa with an affective system of matching layers of bottom, water and ice. Theoretical and experimental investigations showed the possibility of information transfer in a shallow sea under an ice layer. Experimental acoustic system allows one to make measurements in a wide frequency range from 40 to 1100 Hz. The conducted investigation can be used to develop effective remote communication and to model earthquake acoustic precursor measurements.

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The Use of Magnetostrictive Cores for the Vibrations Generation and Energy Harvesting from Vibration, in the Selected Frequencies of Work

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.598.75 ◽

2014 ◽

Vol 598 ◽

pp. 75-80 ◽

Cited By ~ 6

Author(s):

Jerzy Kaleta ◽

Krzysztof Kot ◽

Rafał Mech ◽

Przemyslaw Wiewiorski

Keyword(s):

Energy Transfer ◽

Information Transfer ◽

Wide Frequency Range ◽

Frequency Range ◽

Mechanical Vibrations ◽

Energy Transportation ◽

To Receive ◽

Low Power Electronics ◽

Time Selection ◽

Selection Of

The paper presents research on use of magnetostrictive cores for the recovery of energy from vibrations and its use to power low-power electronics. To achieve this goal a test stand was constructed to generate and to receive the vibrations in the measurement system at the same time. Selection of an appropriate magnetomechanical parameters of the system was an important element influencing end results. The most important were values of the prestress and magnetising field for actuators and harvesters. As a result of the investigation the device operating in a wide frequency range (up to 40 KHz) and a system for energy transportation through mechanical vibrations were developed. Moreover it was shown that the proposed solution allow information transfer in a short bursts over the same system as energy transfer.

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Intensification of mixing of fuel with supersonic air flow when injection and electric discharge are combined

Journal of Physics Conference Series ◽

10.1088/1742-6596/2100/1/012007 ◽

2021 ◽

Vol 2100 (1) ◽

pp. 012007

Author(s):

A A Firsov ◽

A V Efimov ◽

N S Kolosov ◽

I A Moralev ◽

S B Leonov

Keyword(s):

Electric Discharge ◽

Wide Frequency Range ◽

Gas Jet ◽

Experimental Investigations ◽

Oncoming Flow ◽

Frequency Range ◽

Pressure Pulsations ◽

Dc Discharge ◽

Discharge Operation ◽

Mixing Intensification

Abstract This paper presents the results of experimental investigations of DC discharge influence on mixing intensification of transvers injected gas jet into supersonic aiflow. The air was used as injected gas to prevent the influence of chemical reactions on measurements. The data obtained during discharge includes current and voltage acquisition, registration of pressure pulsations in the jet downstream of discharge operation accompanied by correlation and Fourier analysis allowed to conclude that discharge significantly increase the pressure pulsations in a wide frequency range of 1000 Hz to 50kHz. Increase of the oscillations near the jet boundary is assumed to be related to kinematic mixing intensification of the injected gas with the oncoming flow.

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