MEASURING METHOD OF LIQUID LEVEL IN RESERVOIR Russian patent published in 2015 - IPC G01F23/284 

FIELD: measurement equipment.

SUBSTANCE: electromagnetic oscillations are excited in the whole volume of the resonator, the lower part of which has a reduced cross-section, on resonance frequency f_n(x) of the type of oscillations, for which f_n(x) above critical frequency f_ncr of the lower part of the waveguide of the reduced cross-section for the wave of this type, at value x that is lower than some value x₁, at which f_n(x₁) is higher than f_ncr, and f_n(x) is measured, and when value x is higher than x₁, at which f_n(x₁) is lower than f_ncr, electromagnetic oscillations are excited in the resonator volume, except for its lower part of the reduce cross-section, on resonator frequency f_k(x) of the type of oscillations, for which f_k(x) is higher than critical frequency f_kcr of the upper part of the waveguide for the wave of this type, besides, f_kcr<f_ncr, with change of value f_n(x₁) till value f_k(x₁) at x=x₁, and f_k(x) is measured.

EFFECT: improving sensitivity and accuracy of measurements According to the proposed measuring method of liquid level, a vertically waveguide resonator is arranged in the reservoir containing dielectric liquid, the liquid level x in which is equal to its level in the reservoir; electromagnetic oscillations are excited in it and their resonance frequency is measured.

2 cl, 4 dwg