Sentek Instrument LLC products

Distributed acoustic sensing (DAS) is demanded in many applications. Traditionally, fiber optic DAS systems are based on time domain detection of Rayleigh backscatters produced by a laser pulse in the sensing fiber. Due to the extremely weak nature of the Rayleigh scattering, these systems often have an acoustic detection sensitivity limited to the order of nanostrains, as a measure of the minimum detectable acoustic wave.  In addition, the acoustic measurement often has a poor fidelity, and may even become qualitative only as the sensing distance increases, which further weakens the Rayleigh backscatters.   

Dynamic pressure measurement at ultra-high temperatures is highly desirable in many industrial processes. Limited maximum service temperatures of semiconductor transducers or piezoelectric devices force engineers to use either water cooling to the sensors or to employ standoff tubes to guide pressure to a point where these transducers can be used.  Besides increased complexity and cost, the bulky size of the cooled sensors makes access to many locations difficult.  In the meantime, the pressure guiding tubes damp the dynamic signals, which are the true signals for combustion diagnostics and gas turbine compressor stall/surge detection.

Accurate measurement of pressure and temperature in oil/gas and geothermal wells is important to optimized hydrocarbon production and power generation. However, the extreme downhole physical and chemical conditions often challenge the accuracy, stability and reliability of traditional measurement devices.  It is thus desirable to have sensors that can perform well under all aggressive conditions such as high temperature, high pressure, H2S, hydrogen and hydrocarbon/water mixture.