Abstract: A method for generating a temperature-compensated timing signal that includes counting, within an update interval, a first number of oscillations of a first micro-electromechanical (MEMS) resonator, a second number of oscillations of a second MEMS resonator and a third number of oscillations of a digitally controlled oscillator (DCO), computing a target DCO count based on the first number and second number of oscillations, computing a loop error signal based on the target DCO count and the third number of oscillations, and modifying an output frequency of a temperature-dependent (DCO) timing signal based on the loop error signal. The duration of the update interval may also be modified based on temperature conditions, and the update interval may also be interrupted and the output frequency immediately adjusted, if a significant temperature change is detected. Thus, dynamic and precise temperature compensation is achieved that accommodates constant, slowly changing, and rapidly changing temperature conditions.

Abstract: The present invention relates to a method and a system for determining a set of process parameters of a treatment unit in which unit a product is subjected to a temperature treatment, the method comprising: subjecting a product to an electromagnetic signal before, during and/or after a temperature treatment, wherein said electromagnetic signal is adapted to interact with said product dependent upon the dielectric constant distribution of said product, receiving an electromagnetic signal which has interacted with said product, analysing the received electromagnetic signal in comparison with the transmitted electromagnetic signal and thereby determining a response being dependent upon the dielectric constant distribution of said product and based thereupon determine the temperature (distribution) or water content of the product, and analysing said temperature distribution or temperature of the product or products and based thereupon determining a set of process parameters for a temperature treatment in a treatm

Abstract: Disclosed are a temperature measurement apparatus and method for measuring temperature by using RF signals having different frequencies. The temperature measurement apparatus includes a parameter generation unit for generating a first parameter based on a radio frequency (RF) signal having a first frequency and a second parameter based on an RF signal having a second frequency; a parameter detection unit for detecting the generated first and second parameters; and a control unit for calculating a temperature value based on the detected first and second parameters. Accordingly, the temperature measurement apparatus can measure temperature by use of existing components and received RF signals without any addition of a temperature sensor, as well as measure temperature precisely without having any influence on the intensities of RF signals that can vary due to the changes of transmission distances and signal-receiving environments.

Abstract: The invention is a heated thermal probe suitable for use in micro-thermal analysis or other high resolution thermal measurements and actions. The probe is, in the preferred embodiment, a microfabricated cantilever with a sharp probe tip of a type used in Scanning Probe Microscopes (SPM's) which further includes an integral resistive heating element. The heating element is formed by doping regions of the cantilever with an ion implant process to make lower resistance connections and a higher resistance heating element. There is no spatial overlap between the base of the probe tip and the heating element or conductors.

Abstract: An ultrasonic diagnostic apparatus includes an ultrasonic probe having a plurality of transducers arranged and a plurality of temperature sensors located along a direction of arranging the transducers, and a temperature calculation device for obtaining a maximum temperature on the basis of the detected temperatures of the plurality of temperature sensors.

Abstract: Ultrasound transducer temperatures are measured in response to a temperature dependent property of the ultrasound transducer. The temperature is measured without addition of new electronics or hardware retrofits of the transducer. By implementing software and/or hardware on the ultrasound system rather than the transducer, the temperature is measured in order to provide a level of fault protection. The upgraded or new ultrasound system uses either old or new transducers while still providing temperature measurement. For example, the temperature of the lens or window is measured as a function of changes in attenuation or acoustic velocity. The receive beamformer already implemented on many ultrasound systems is used to measure a temperature dependent property of the lens or window. As another example, the dielectric constant or capacitance of one or more transducer elements is measured using additional hardware in the ultrasound system.

Abstract: A system for measuring the height of bin content includes a transmitter for transmitting an acoustic pulse towards the upper surface of the content, a non-collinear receiver array for receiving an echo of the pulse and producing signals in response to the echo, and a processing apparatus for computing one or more directions of arrival of the signals from the upper surface to the array along with corresponding measured distances. Preferably, the receivers are transducers that also serve as transmitters. Two or more such measured distances constitute a map of the upper surface for estimating the quantity of the bin content. Preferably, the system includes a pulse shaper and repeater for optimizing the pulse shape relative to the signals.

Abstract: A thermometer is provided. A housing has at least one opening. A dielectric element is disposed in the housing. At least one microwave guide is coupled to the at least one opening for providing a signal into the dielectric element for propagation at a resonant frequency and for receiving the signal from the dielectric element. A temperature determination unit receives the signal from the at least one microwave guide, measures the resonant frequency of the dielectric element, and determines the temperature of the dielectric element based on a relationship between resonant frequency and temperature of the dielectric element.

Abstract: A first thermometry system for measuring a temperature of an object under test includes a first detecting sheet having crystal oscillators arranged on a first sheet-like object formed of resin, and a first measuring device for measuring the temperature based on frequencies acquired from the crystal oscillators and corresponding to natural frequencies of the crystal oscillators. In this system, the first detecting sheet is placed in contact with the object under test, whereupon the crystal oscillators provide the natural frequencies corresponding to the temperature of the object under test. The first measuring device measures the temperature of the object under test accurately based on the frequencies corresponding to the natural frequencies.

Abstract: An acoustic pyrometer measures the average gas temperature across a space of known distance, especially turbulent, high temperature gas loaded with caustic particulates. It includes an acoustic signal generator that generates a high amplitude acoustic signal with a short rise time The acoustic signal generator includes an outer tank closed at top and bottom ends by top and bottom end walls and enclosing an outer chamber. A cylinder is supported within the tank and has top and bottom opposed ends. A mid-plate extends across the cylinder and defines the bottom end, and an axial opening in the mid-plate receives a shaft of a piston assembly having an upper piston and a lower piston at ends of the shaft. A throat is attached to the bottom end, and receives the lower piston. The lower piston seals the throat when received in the throat. The upper piston is slidable in the cylinder under influence of air pressure.

Abstract: A temperature measurement system is characterized by at least one passive surface acoustic wave (SAW) temperature sensor. The sensor includes at least one piezoelectric substrate having an interdigital SAW transducer disposed upon the piezoelectric substrate for conversion of an RF signal into an acoustic wave and vice versa. At least three additional SAW elements are also disposed on the substrates in a manner such that they define two acoustic propagation paths that are non-parallel relative to the crystal axes of the substrates, and such that the temperature coefficients of delay in the two tracks differ. The SAW elements receive a signal from the SAW transducer and produce response signals. The response signals combine to produce a signal with a power spectral density such that the integrated power within each of two specified portions of the spectrum provides an indicator of the temperature.

Abstract: An apparatus for sensing a change in environmental conditions is disclosed. The apparatus includes a coating or a wire between two surfaces that has a mechanical property changed as a result of a change in the environmental conditions. The change in the mechanical property of the coating or wire results in a change in a vibration characteristic of the apparatus, such as the frequency, phase, amplitude or quality factor. The change in the vibration characteristic can be used to determine the change in the environmental condition.

Abstract: The invention relates to a device and a method for detecting a fault in a measurement device comprising a resonator and means for measuring a resonant frequency of the resonator. According to the invention, the device further includes means delivering information (S3) representative of the quality factor of the resonator (3) at the resonant frequency.

Abstract: Acoustic temperature measurement at a remote location is provided. An acoustic source transmits acoustic radiation to an acoustic receiver along an acoustic path. The path passes through or near the remote location. The temperature is non-uniform along the path. A change in an integrated acoustic delay between the source and receiver along the path is measured. This acoustic delay can be either a phase velocity delay or a group velocity delay. The temperature at the remote location is determined by relating the measured change in integrated acoustic delay to the remote location temperature with a combined thermal-acoustic model. The combined model relates temperature to acoustic propagation velocity along the path. The combined model preferably includes temperatures of the source and receiver locations, and a heat source geometry at the remote location.

Abstract: A temperature measurement technique for calculating a temperature in a high temperature environment by monitoring a change in resonant frequency of a resonant structure loaded with a dielectric material. A response curve for a reflection coefficient S11 associated with the resonant structure is generated, typically by the use of a network analyzer connected to the resonant structure via a cable. A minimum point for the response curve is identified to detect the resonant frequency for the resonant structure. A calibration map is applied to the minimum point to identify a temperature associated with the resonant frequency of the resonant structure. The temperature associated with the resonant frequency of the resonant structure represents the temperature of the high temperature environment.

Abstract: The present application discloses a method of estimating a surface temperature of an ultrasound probe having a plurality of transducer elements and a surface, involving: a) establishing a temperature rise function of the surface of the ultrasound probe due to a single active transducer element; b) selecting one of the transducer elements; c) applying a single transmission pulse signal to the selected transducer element such that the selected transducer element operates once; d) measuring a temperature rise of the surface of the ultrasound probe at predetermined positions on the surface thereof; e) completing the temperature rise function based on the measured temperature rise; and f) estimating a temperature rise of the surface of the ultrasound probe based on the temperature rise function.

Abstract: A substrate for temperature measurement has seventeen temperature measuring elements mounted thereto and each having a built-in quartz resonator. Each of the temperature measuring elements is connected to one coaxial cable covered with fluorocarbon resin having excellent heat resistance. The seventeen cables are bonded to the substrate for temperature measurement using an adhesive so that all the paths of the cables from their contacts with the temperature measuring elements to their boundary points to the outside of the substrate run on the upper surface of the substrate for temperature measurement, and that they are made to have a substantially equal length from their contacts to their boundary points. This minimizes and makes uniform thermal disturbances given to each of the temperature measuring elements from the cables, thus enabling high-precision substrate temperature measurement.

Abstract: In a temperature sensor, especially in a temperature sensor using a resonator, based on a frequency of one oscillator circuit (resonator), frequencies of the other one or more oscillator circuits (resonators) are measured, and frequency-temperature characteristics of a plurality of resonators are synthesized in order to realize an accurate temperature sensor which does not require an accurate frequency reference regardless of a temperature change, and has a linear characteristic and a wide measurable temperature range. Also, two oscillator circuits have two resonators respectively with quadratic characteristics in which quadratic coefficients are the same and linear characteristics are different from each other, and a difference between oscillation frequencies of both oscillator circuits is obtained.

Abstract: This invention utilizes the nuclear magnetic resonance imaging and spectroscopy to experimentally measure thermal diffusivity, thermal conductivity, specific heat, specific absorption rate, thermal power, heat transfer coefficient, heat of reaction and the membrane permeability in substances and systems.

Abstract: Ultrasound transducer temperatures are measured in response to a temperature dependent property of the ultrasound transducer. The temperature is measured without addition of new electronics or hardware retrofits of the transducer. By implementing software and/or hardware on the ultrasound system rather than the transducer, the temperature is measured in order to provide a level of fault protection. The upgraded or new ultrasound system uses either old or new transducers while still providing temperature measurement. For example, the temperature of the lens or window is measured as a function of changes in attenuation or acoustic velocity. The receive beamformer already implemented on many ultrasound systems is used to measure a temperature dependent property of the lens or window. As another example, the dielectric constant or capacitance of one or more transducer elements is measured using additional hardware in the ultrasound system.

Abstract: An apparatus for managing the temperature of an integrated circuit having a multiple core microprocessor is described. Specifically, thermal sensors are placed at potential hot spots throughout each microprocessor core. A thermal management unit monitors the thermal sensors. If a thermal sensor identifies a hot spot, the thermal management unit adjusts the operating frequency and voltage of that microprocessor core accordingly.

Abstract: A radio frequency temperature sensor and a method of calibration temperature therefor are disclosed. An active radio frequency temperature sensor including a ring oscillator, a memory, a frequency counter, a radio frequency transmission interface and a micro-controller is used to calibrate and verify the efficacy of the radio frequency temperature sensor. Thereafter, a passive radio frequency temperature sensor including a regulator, a clock extractor, a ring oscillator, a memory, a frequency counter, a modulator and a state-machine is developed according to the verified results.

Abstract: A method and apparatus for sensing temperature using optical fiber is provided. In one embodiment, a method for sensing temperature using optical fiber includes launching a polarized optical signal having sufficient intensity to produce Brillouin scattering of the signal into a polarization maintaining optical fiber, receiving a first signal reflected from the launched signal, receiving a second signal reflected from the launched signal; and resolving a metric indicative of temperature from the first and second received signals. The method is particularly useful for sensing temperature in hazardous locations such as down hole gas and oil field applications or other applications where minimization of strain effects to signal transmission is desired.

Abstract: A method of determining the temperature inside a combustion liner without making a direct measurement of the actual temperature. The technique is based on a measurement of the frequency of one of the transverse acoustic modes occurring inside the combustion chamber. The frequency is determined from the transverse geometric dimensions of the combustion chamber and the speed of sound in the gas inside the combustion chamber. The speed of sound in the gas is known from thermodynamics to be a function of gas temperature and gas properties. Thus, from a measurement of the resonant frequency and knowing the combustor dimensions and gas properties, the temperature can be determined with accuracy.

Abstract: A device and a system for measuring temperature in an inaccessible and/or movable mechanical part. The device comprises a temperature-sensitive clement which can be installed inside the movable part and which is designed to emit a signal containing information on the temperature of said clement, in such a way that this signal can be received by a control unit. The temperature-sensitive clement is a SAW chip which is arranged at the lower end of a hole in the mechanical part whose temperature is to be measured and it is connected to a first antenna provided outside said hole in said mechanical part.

Abstract: A method and apparatus for sensing temperature using optical fiber is provided. In one embodiment, a method for sensing temperature using optical fiber includes launching a polarized optical signal having sufficient intensity to produce Brillouin scattering of the signal into a polarization maintaining optical fiber, receiving a first signal reflected from the launched signal, receiving a second signal reflected from the launched signal; and resolving a metric indicative of temperature from the first and second received signals. The method is particularly useful for sensing temperature in hazardous locations such as down hole gas and oil field applications or other applications where minimization of strain effects to signal transmission is desired.

Abstract: An apparatus and method are provided for sensing a physical stimulus of an integrated circuit. The apparatus and method allow for accurate die temperature measurements of the integrated circuit and are able to provide a highly accurate die temperature measurement without the need for an independent voltage source or current source.

Abstract: A method for evaluating the Wobbe index of a fuel gas belonging to a family of gases. The method includes measuring mass flow rates the fuel gas and of a reference gas, which is not necessarily a fuel gas at respective absolute pressures and temperatures and in a sonic flow through a microjet. An evaluation of the Wobbe index (W) of the fuel gas as W=A×Y+B uses the results of measurements of the fuel gas and the reference gas and is established for all the gases of the family considered.

Abstract: An apparatus (10) for performing acoustic thermography including a fixture (32) having a compliant member (40) that allows contacting surfaces of a horn face (20) and a specimen surface (16) to self-align into parallel contact in response to only the contacting force (FC) there between. When the contacting surfaces are brought together in a slightly non-parallel alignment, the contacting force develops a force component (FN) that is normal to the plane of contact. This normal force causes deflection of a compliant member, thereby providing movement that brings the contacting surfaces into parallel alignment. The compliant member may be a spring (48), elastomer (50), swivel member (56), bearing member (80), or a curved non-stick surface (90) in various embodiments.

Abstract: The present invention provides an integrated circuit VLSI temperature system for the calibration of threshold temperatures. A temperature sensitive ring oscillator (TSRO) generates a TSRO calibration parameter. A memory is employable to store the TSRO calibration parameter. A module is employable to determine a threshold TSRO oscillation frequency from the TSRO calibration parameter. A memory is employable for storing at least one threshold TSRO oscillation frequency.

Abstract: An acoustic pyrometer measures the average gas temperature across a wide space of known distance, especially turbulent, high temperature gas loaded with caustic particulates. It includes an acoustic signal generator that generates a high amplitude acoustic signal with a short rise time and a detector positioned adjacent the signal generator that detects the onset of the acoustic signal in the signal generator and generates a first electrical signal corresponding in time to the onset of the acoustic signal in the signal generator. A receiver, positioned across the space from the signal generator, receives acoustic signals from the space and generates electrical signals corresponding to amplitude and frequency of the acoustic signals received in the receiver.

Abstract: Ultrasound transducer temperatures are measured in response to a temperature dependent property of the ultrasound transducer. The temperature is measured without addition of new electronics or hardware retrofits of the transducer. By implementing software and/or hardware on the ultrasound system rather than the transducer, the temperature is measured in order to provide a level of fault protection. The upgraded or new ultrasound system uses either old or new transducers while still providing temperature measurement. For example, the temperature of the lens or window is measured as a function of changes in attenuation or acoustic velocity. The receive beamformer already implemented on many ultrasound systems is used to measure a temperature dependent property of the lens or window. As another example, the dielectric constant or capacitance of one or more transducer elements is measured using additional hardware in the ultrasound system.

Abstract: In a method and an arrangement for acoustic determination of an instantaneous fluid temperature, acoustic velocity V in a fluid is monitored and an output signal related to the acoustic velocity is generated. A conventional temperature sensor senses a fluid temperature TS and generates an output signal related thereto.

Abstract: In a method apparatus for measuring the temperature of a semiconductor substrate during processing thereof in a processing chamber, a resonant circuit formed on the substrate surface is energized by an electromagnetic field radiation device, and disturbances in the electromagnetic field are detected to determine the resonant frequency of the resonant circuit. The temperature of the substrate is determined as a function of the resonant frequency. The substrate is moved into and out of processing chamber by a transfer arm, and the radiation device is disposed on the transfer arm or mounted on the processing chamber. Multiple resonant circuits may be provided, which are energized by movement of the transfer arm, without transferring the substrate.

Abstract: The present invention relates to a method, a measuring cell and a system for measuring very small heat changes in a sample. The system comprises a measuring cell 16 for containing the sample during the measurement process, at least one electromagnetic radiation unit 14 for radiating one or several samples with modulated monochromatic or polychromatic radiation 46 inside said measuring cell 16. Said measuring cell 16 comprises at least one acoustic transducer 22 for generating a first output signal V(t) and at least one heat measuring device 24 for generating a second output signal T(t). Both signals are connectable to a combining unit 18 that generates an information signal by means of a reference signal f(t). Said information signal is connectable to a signal processing unit 20 for determining at least one relevant reaction parameter as a function of the measured heat change.

Abstract: An anomalous arc discharge detection apparatus, including multiplicity of ultrasonic detectors placed at different sections of a plasma processing chamber such that an ultrasonic wave accompanying an anomalous discharge is detected by the ultrasonic detectors at different propagation times or with different delay times. The detected signals are compared with each other on the same time axis to obtain the maximum range of variation of the detected waveforms and the differences in delay time of the respective ultrasonic detectors. From the comparison of the maximum range of variation and the delay times of the ultrasonic detectors, the position of the source point, and the level as well, of the anomalous arc discharge are determined, which can be displayed on a monitor and utilized to issue an alarm if necessary.

Abstract: An apparatus for detecting the temperature of a room (2) includes means (4) for generating and receiving sound waves, means (5) for determining the transit time of the sound waves for a certain distance (x) in the room (2) and means (10) for calculating the temperature (U) of the room (2) by means of the ascertained transit time (t) of the sound waves for the distance (x) in the room (2). An approximation procedure for ascertaining the distance (x) is automatically executed. The temperature (U) ascertained in that way corresponds to a mean room temperature over the distance (x).

Abstract: An acoustic pyrometer measures the average gas temperature across a wide space of known distance, especially turbulent, high temperature gas loaded with caustic particulates. It includes an acoustic signal generator that generates a high amplitude acoustic signal with a short rise time and a detector positioned adjacent the signal generator that detects the onset of the acoustic signal in the signal generator and generates a first electrical signal corresponding in time to the onset of the acoustic signal in the signal generator. A receiver, positioned across the space from the signal generator, receives acoustic signals from the space and generates electrical signals corresponding to amplitude and frequency of the acoustic signals received in the receiver.

Abstract: An acoustic pyrometer measures the average gas temperature across a wide space of known distance, especially turbulent, high temperature gas loaded with caustic particulates. It includes an acoustic signal generator that generates a high amplitude acoustic signal with a short rise time and a detector positioned adjacent the signal generator that detects the onset of the acoustic signal in the signal generator and generates a first electrical signal corresponding in time to the onset of the acoustic signal in the signal generator. A receiver, positioned across the space from the signal generator, receives acoustic signals from the space and generates electrical signals corresponding to amplitude and frequency of the acoustic signals received in the receiver.

Abstract: An apparatus for managing the temperature of an integrated circuit having a multiple core microprocessor is described. Specifically, thermal sensors are placed at potential hot spots throughout each microprocessor core. A thermal management unit monitors the thermal sensors. If a thermal sensor identifies a hot spot, the thermal management unit adjusts the operating frequency and voltage of that microprocessor core accordingly.

Abstract: A magnet is provided to a vibrating plate within a detection pipe unit and an electromagnet is placed opposite to the magnet with a slight gap therebetween. A drive circuit applies, to a coil at every predetermined measurement cycle, an alternating current at a frequency which is swept over a predetermined range centered at a resonance frequency of the vibrating plate. When the alternating current is applied, a phase comparison circuit detects a change in phase that is caused according to whether or not an object contacts the vibrating plate. A microcomputer determines presence/absence of the object based on the detected change in phase, measures the temperature based on the detected change in phase in a former half cycle of the predetermined measurement cycle and changes the swept frequency based on the result of measurement of the temperature in a latter half cycle of the predetermined cycle.

Abstract: A device, method and system for sensing the temperature of an environment. An image sensor may be introduced into an environment having an image sensing module. The dark current noise of the image sensor may be sensed, and the temperature of the image sensor (and environment) calculated. Such a device, system and method may be used in, for example, a medical imaging device.

Abstract: The invention relates to a fiber-optic temperature sensor which is provided with a preferably spherical microparticle with a diameter in the range of from 5 to 100 micrometers as the optical resonator. Said microparticle is linked with optical waveguides for coupling light in or out. A laser diode (1) incites optical resonances in the microparticle, the wavelengths of these resonances depending on the diameter of the microparticle. Due to the thermal expansion of the microparticle, said diameter in turn depends on the temperature. The temperature sensor is calibrated so that the resonance wavelengths can be correlated with corresponding temperature values.

Abstract: A mechanical resonator device which has a phenomena-dependent electrical stiffness is provided. The phenomena may be temperature or acceleration, for example. The device includes a substrate and a resonator supported above the substrate by supports. The device further includes an electrode supported above the substrate adjacent the resonator by supports to obtain an electrode-to-resonator gap wherein electrical stiffness generated across the gap is phenomena-dependent to take instability of resonant frequency of the device caused by the phenomena into consideration.

Abstract: A transducer assembly for measurement of downhole temperature and (if required) pressure includes a crystal resonator responsive to temperature and a pair of temperature sensors such as thermocouples or RTDs. One sensor is located with the crystal resonator and the other is exposed to external conditions such as those adjacent the pressure resonator. Thus, the sensors provide a correction signal for the resonator and allow improvement in the transient response of the transducer. A feedback circuit for correcting the resonator output is also disclosed.

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.

Abstract: Ultrasonic transducers and tomographic techniques determine the temperature of a semiconductor substrate holder at all points on the substrate holder, thereby allowing comprehensive real-time control of the temperature of the substrate holder during a process, such as a semiconductor wafer etching process. An apparatus for measuring temperatures of respective portions of a substrate holder that supports a substrate (e.g., a semiconductor wafer) on which a process (e.g., an etching process) is carried out, and for controlling the temperatures of the respective portions in response to the measured temperatures, includes: an arrangement of at least one ultrasonic transducer arranged and configured to transmit ultrasonic energy through the substrate holder, and a data processor configured to calculate, during the process, the temperatures of the respective portions of the substrate holder based on respective propagation time delays of the ultrasonic energy through the respective portions.

Abstract: A substrate temperature measuring method, a substrate processing method, substrate temperature measuring equipment and semiconductor manufacturing equipment that can measure more accurately a temperature of and can process more precisely a substrate than in existing ones are provided. Electric energy is converted into electromagnetic wave energy, an electromagnetic wave involving the converted electromagnetic wave energy being irradiated on a resonant circuit disposed on a substrate. A voltage or a current involving electric energy is detected to detect a resonance frequency of a resonant circuit. From the detected resonance frequency, a temperature of a substrate is obtained. Thereby, by making use of at least one resonant circuit disposed on a substrate, a temperature of the substrate can be measured with high precision.

Abstract: An acoustic temperature measurement system for pipeline fluids comprises a loudspeaker (16) with spaced microphone (18) in a sealed pipe (10) with end cap (11). A computer arrangement (22) provides a tone burst signal which drives the speaker via power amplifier (21) and the outgoing and reflected signal is detected by the microphone (18) and following amplification in amplifier (20) passes to the computer (22) for processing. The signals are processed to determine phase relationships indicative of temperature and can be used in correcting leakage measurement readings.

Abstract: An acoustic pyrometer measures the average gas temperature across a wide space of known distance, especially turbulent, high temperature gas loaded with caustic particulates. It includes an acoustic signal generator that generates a high amplitude acoustic signal with a short rise time and a detector positioned adjacent the signal generator that detects the onset of the acoustic signal in the signal generator and generates a first electrical signal corresponding in time to the onset of the acoustic signal in the signal generator. A receiver, positioned across the space from the signal generator, receives acoustic signals from the space and generates electrical signals corresponding to amplitude and frequency of the acoustic signals received in the receiver.