Abstract: The present disclosure provides a method and an apparatus for measuring electrical conductivity of liquids. In one aspect, the apparatus includes a waveform generator module configured to generate a first waveform signal and to supply the first waveform signal to a sensor; a phase adjustment module configured to receive the first waveform signal from the waveform generator module and to generate a phase-shifted signal from the first waveform signal, said phase-shifted signal having a phase that is adjusted based upon expected or measured properties of the liquid and further adjusted to eliminate phase error induced inaccuracies in the measurement; and a signal combination module configured to receive a return signal from the sensor and the phase-shifted signal from the phase adjustment module and to sum the return signal and the phase-shifted signal to produce an adjusted return signal containing information associated with the electrical property of the liquid.

Abstract: The present disclosure provides a method and an apparatus for measuring electrical conductivity of liquids. In one aspect, the apparatus includes a waveform generator module configured to generate a first waveform signal and to supply the first waveform signal to a sensor; a phase adjustment module configured to receive the first waveform signal from the waveform generator module and to generate a phase-shifted signal from the first waveform signal, said phase-shifted signal having a phase that is adjusted based upon expected or measured properties of the liquid and further adjusted to eliminate phase error induced inaccuracies in the measurement; and a signal combination module configured to receive a return signal from the sensor and the phase-shifted signal from the phase adjustment module and to sum the return signal and the phase-shifted signal to produce an adjusted return signal containing information associated with the electrical property of the liquid.

Abstract: The ultrasonic thermometer system of the present invention includes a rod or probe of high temperature, grain-stabilized material that has a magnetostrictive or piezoelectric transducer bonded to one end. The transducer is excited by a transducer driver, creating short, periodic, ultrasonic pulses that travel down the length of the rod in a “pulse-echo” fashion. Along the length of the rod, circumferential grooves are cut which reflect some of the ultrasonic energy back to the transducer thus creating a reflected or echo signal. Two such reflected signals from two adjacent grooves, or a signal from one groove and a signal from the end of the rod, establish a temperature zone. This is the zone of interest to the user, which would be inserted into the user's process that needs to have the temperature monitored.