FIELD: physics; geophysics.
SUBSTANCE: invention relates to geoexploration and can be used to determine different properties of hydrocarbon formation fluids. The invention discloses examples of methods, apparatus and articles of manufacture for process measurements of strings vibrating in fluids. A disclosed example of an apparatus includes a downhole assembly and a surface assembly. The downhole assembly 300 includes a sensor 305, 325 for measuring a waveform representative of a motion of a string vibrating in a fluid at a downhole location in a wellbore, a waveform simulator 332 for computing a model parameter based on the measured waveform, and a first telemetry module 340 for transmitting the computed model parameter to a surface location. The surface assembly includes a second telemetry module for receiving the computed model parameter from the downhole assembly, and a viscosity analyser for estimating a viscosity of the fluid based on the computed model parameter. The method of processing measurements of strings vibrating in a fluid involves an operation for measuring a waveform and computing a model parameter of vibration of the string based on the measured waveform. Said model parameter is used to determine viscosity of the formation fluid.
EFFECT: high accuracy of determining properties of formation fluids.
32 cl, 7 dwg
