A system and method for an aircraft includes an air data system and an acoustic sensing system. The air data system includes a pitot tube positioned to sense a pitot pressure of an airflow about an exterior of the aircraft, and an angle of attack vane positioned to sense an angle of attack of the aircraft. The pitot pressure and the angle of attack are used to determine first air data parameters. The acoustic sensing system is configured to emit acoustic signals about the exterior of the aircraft and sense the acoustic signals as sensed data. The sensed data is used to determine second air data parameters.

An apparatus and method for measuring air flow in a duct, e.g. in a ventilation duct, includes a sensor fittable into connection with the duct, the sensor including an ultrasound transmitter and at least two ultrasound receivers, and a control unit to which the ultrasound transmitter and ultrasound receivers are connectable. The control unit is adapted to measure, during the measuring of air flow, the phase difference of an ultrasound signal received at the same moment in time by at least two ultrasound receivers fitted into connection with the duct and, based on the measured phase difference, to determine the flow velocity and/or flow direction of the air. The apparatus is adapted to perform a calibration of the apparatus by transmitting with an ultrasound transmitter at least one calibration signal and by receiving the calibration signal with at least two ultrasound receivers. The apparatus is further adapted to analyze the received calibration signal and based on the analysis to select the parameters to be used in measuring to be such that at least one analysis result of the calibration signal meets predetermined criteria with the parameters.

The present invention provides a wind measurement apparatus based on 3D (three dimensional) non-orthogonal ultrasonic sensor array, the ultrasonic sensor array is composed of two group of ultrasonic sensors, which are centrosymmetrically located at opposite sides, and the angle formed by connecting any two ultrasonic sensors at a side to the symmetry point O is less than 90, the arrangement of 3D non-orthogonal ultrasonic sensor array reduces the generation of turbulence, thus, the accurate wind speed and wind direction is obtained. In the mean time, the central channel is employed to obtain a reference wind speed v.sub.ref. Comparing the speed component v.sub.central along central channel of the wind under measurement with the reference wind speed v.sub.ref, if the difference is less than a present threshold, then computing module outputs the measurement results, or discards them, thus the wind measurement accuracy is further improved.

An assembly and method for using ultrasonic wind sensors and their assembly with solar cell technology is disclosed. The weather sensor assembly may include a sensor module with a top sensor and a bottom sensor, where the top sensor and the bottom sensor are separated by a gap to allow air to flow through unobstructed. By including an unobstructed gap in the sensor module structure, ultrasonic signals communicated by the ultrasonic wind sensors to obtain wind measurements are less subject to comprise from signal interference, thereby improving accuracy. Additionally, one or more power modules may be included that provide power storage and power generation capabilities, which are then placed beneath the sensor module. By doing so, multiple power modules can be stacked vertically on top of one another to ensure that ultrasonic wind sensors, which typically require high power, are powered more efficiently.

An angle-of-attack sensor includes at least one acoustic transmitter is configured to provide an acoustic pulse. The first acoustic receiver is positioned at a radial distance from the at least one acoustic transmitter. The first acoustic receiver is configured to receive the acoustic pulse at a first time and provide a first receiver signal. The second acoustic receiver is positioned at the radial distance from the at least one acoustic transmitter aligned with an axis that extends through the at least one acoustic transmitter and the first acoustic receiver. The second acoustic receiver is configured to receive the acoustic pulse at a second time and provide a second receiver signal. The angle-of-attack circuitry is configured to determine a delay difference between the first and second receiver signals representative of a difference between the first time and the second time and determine an angle-of-attack based upon the delay difference.

Systems and devices for airflow measurements in rooms and air delivery ducts with low-cost, low-power, accurate, calibration-free, and compact wireless airflow sensors are provided. The system uses room and duct flow sonic anemometers and processing to measure air velocities and temperatures as well as allow control over the environmental conditioning systems. The anemometers use arrays of transmitter/receivers to simultaneously measure multiple sound paths and determine velocity vectors and volumetric flow paths. By transmitting in both directions along the paths between transceivers, differential times of flight (TOF) are measured. These determine both the velocity and temperature of the air along each path.

A method and system may be used to measure the fluid flow rate of fluid in a pipeline. In the method and system, a signal may be transmitted by a transducer into the pipeline. The signal may be reflected by the contents of the pipeline and received by a receive transducer. Operations may be performed on the received signal to determine the fluid flow rate.

A system and method of non-intrusive thrust measurement of a gas turbine engine. The system comprises a transmitter disposed at a boundary of fluid flow and at least one receiver adapted to receive transmissions from the transmitter. A processor is coupled to the receivers to determine a parameter from a characteristic of the transmission at the receiver suite and adapted to determine a thrust parameter from the parameter. A method for non-intrusively measuring engine thrust includes transmitting a wave across the exhaust plume, receiving the transmitted wave and determining a measurement parameter of the exhaust plume based on a characteristic of the received wave, and comparing the measurement parameter to a reference parameter and determining the thrust based on the comparison.

The invention relates to a method and an arrangement for an ultrasound clamp-on flow measurement according to the transit-time method. The problem addressed by the invention is to provide a measurement arrangement for clamp-on flow measurement, which enables measurement using only two pairs of acoustic transducers in both reflection configuration and in X configuration, without requiring the acoustic transducer position to be changed when switching between configurations. For the method according to the invention, at least four acoustic transducers are arranged on a measurement pipe, which are controlled in such a way that the flow measurement is performed consecutively in an alternating manner in the X configuration and in the reflection configuration. For this purpose, two acoustic transducers are connected for each transmission-receiving pair for a flow measurement in X configuration, and/or two acoustic transducers are connected for each transmission-receiving pair for two reflection configurations.

An ultrasonic flow meter (UFM) includes a first and second ultrasonic transducer for attaching to a pipe, and a transceiver coupled to the transducers by a multiplexer. A controller having an associated memory runs an adaptive multi-frequency hopping and coding algorithm that selects ?1 frequency to be hopped within the measured transducer impedance spectrum using a threshold level that selects at least a peak for the phase or a valley for the magnitude, and selects a coding scheme for the chosen frequency to provide a coded frequency sequence. A received signal generated responsive to an ultrasonic signal with the coded frequency sequence into the fluid is decoded, and peak detection is performed on the decoded received signal. The travel time is calculated from the decoded signal, and a speed of the fluid is then determined from the travel time.