A METHOD AND AN ULTRA-SOUND DEVICE FOR A WAVE PROFILE MEASUREMENT IN REAL TIME ON THE SURFACE OF LIQUID, PARTICULARLY IN A MODEL BASIN

摘要

A method of wave profile measurements in real time on a liquid surface, particularly in a model basin, including placement of an ultra-sound probe above the liquid surface and a measurement of time required for the ultra-sound signal to cover the distance from the probe generator to the measurement point specified on the surface of the liquid and back to the absorbing element of the probe, followed by recording the results of the measurements and re-creation of the wave profile within a two-dimensional space as a time profile of distance from the measurement point determined by the probe, with at least two ultra-sound probes placed along an axis parallel to the direction of wave propagation above the tested liquid surface, at a mutual distance not greater than the minimum width of the detection area of a single probe, and the received signal is processed in an amplifiers and comparators circuit, a multiplexer circuit and in a sample- and-hold circuit, generating the output signal the voltage of which corresponds to the height of a momentary deformation of the free surface, correlated with the distance between the ultra-sound probe and the tested surface, whilst the voltage profile corresponds to the wave profile measured on the liquid surface, with the last voltage signal with a value within a pre-set, permitted value range set as a function of the accepted sensitivity is used as the output signal, and the signal received from the probe with the smallest distance from the measurement point on the surface of the tested liquid at the time of the measurement receives the highest priority. A device executing the method according to the invention, including a transmitting-receiving ultra-sound probe connected to a processing device, which includes at least one receiving ultra-sound probe (S1, S3) located near the transmitting-receiving ultrasound probe (S2) and at a distance not greater than the minimum width of the detection area of a single probe, while the processing device (9) is equipped with an amplifiers and comparators circuit (1), connected to a multiplexer circuit (2), a comparator circuit (3) and a sample- and-hold circuit (4) and to the device output (5).