Laser meter for hydrosphere pressure variations with a mechanical temperature compensation system

2020

JMSE

In the article we analyzed the results of processing experimental data of the range of surface gravity sea wind waves (2–20 s) and the range of infragravitational sea waves (30 s–10 min), obtained on the laser meter of hydrosphere pressure variations. The laser meter of hydrosphere pressure variations was installed for a long time on the bottom at different points of the Sea of Japan shelf. This paper presents the results of the analysis of swell waves caused by the KOMPASU typhoon, which passed over the Sea of Japan on 2–3 September 2010. Several mechanisms of the generation and propagation of waves with different periods during the typhoon movement are considered. In the course of the analysis, we studied the connection between variations of the main periods of gravitational sea waves with the dispersion and the Doppler effect, variations of speed and direction of the wind in a typhoon zone. The nonlinearity of the process of wave period change caused by dispersion is estimated. In the combined analysis of variations of hydrosphere pressure in the ranges of gravitational and infra-gravitational sea waves, we studied their energy relationships and determined regional infragravitational sea waves, which make a significant contribution to the energy of the infragravitational range.

Section: Experimental Datamentioning

confidence: 99%

Fluctuations of the Sea Level, Caused by Gravitational and Infra–Gravitational Sea Waves

2020

JMSE

“…All of the experimental data presented in this work were obtained using laser meters of hydrosphere pressure variations [31]. These devices were installed on the bottom for a period from several days to several months, transmitting data in real time to laboratory rooms located at Shultz Cape, the Sea of Japan, in the Primorsky Territory of the Russian Federation.…”

Section: Introductionmentioning

confidence: 99%

Method of Studying Modulation Effects of Wind and Swell Waves on Tidal and Seiche Oscillations

2021

JMSE

This paper describes a method for identifying modulation effects caused by the interaction of waves with different frequencies based on regression analysis. We present examples of its application on experimental data obtained using high-precision laser interference instruments. Using this method, we illustrate and describe the nonlinearity of the change in the period of wind waves that are associated with wave processes of lower frequencies—12- and 24-h tides and seiches. Based on data analysis, we present several basic types of modulation that are characteristic of the interaction of wind and swell waves on seiche oscillations, with the help of which we can explain some peculiarities of change in the process spectrum of these waves.

“…It should have both the highest sensitivity and the best frequency and dynamic ranges. At present, based on the use of modern laser-interference methods, an instrument has been created for measuring the hydrosphere pressure variations in a wide frequency and dynamic range [20]. Unlike the devices created earlier, this device is based on the equal-arm Michelson interferometer, which made it possible to increase its accuracy by several orders of magnitude.…”

Section: Introductionmentioning

confidence: 99%

Supersensitive Detector of Hydrosphere Pressure Variations

et al. 2020

Sensors

This paper presents an instrument based on an equal-arm Michelson interferometer and a frequency-stabilized helium-neon laser. It is designed to record hydrosphere pressure variations in the frequency range from 0 (conventionally) to 1000 Hz, with accuracy of 0.24 mPa at sea depths of up to 50 m. The operating range of the instrument can be increased by order of magnitude by improving the registration system speed, and accuracy can be enhanced by using larger diameter membranes and/or their smaller thickness. The paper demonstrates some experimental results obtained on the supersensitive detector of hydrosphere pressure variations, confirming its high performance in the infrasonic and sonic ranges.