546results about "Fluid speed measurement using pressure difference" patented technology

A method, apparatus, and computer program product for identifying air data for an aircraft. The lift for the aircraft is identified. The number of surface positions for the aircraft is identified. The angle of attack during flight of the aircraft is identified. A synthetic dynamic pressure is computed from the lift, the number of surface positions, and the angle of attack.

An apparatus and a method used to determine the speed and direction of the wind experienced by a wind turbine are provided. The apparatus comprises at least one sensor fixed to the rotor of the wind turbine, an angular sensor to measure the angular position of the rotor of the wind turbine, and a circuit which converts the relationship between the output of the at least one sensor and the output of the angular sensor into the speed and direction of the wind experienced by the wind turbine. According to the invention, the sensing apparatus can measure the wind speed and direction in three dimensions. In addition, mounting the sensors directly to the rotor of the wind turbine results in a very simple and robust installation. Mounting the sensors directly to the rotor also eliminates the turbulence from the rotor and the nacelle of the wind turbine from affecting the sensors.

The present invention provides restrictive-flow flow measurement devices, valve improvements and signal control devices and processes that control the flow of liquids, including control processes for single-liquid calibration.

A pitot pressure sensing probe assembly is made up of individual components comprising a barrel formed with a longitudinal interior passageway and a conical end cap at its leading end. A strut that has stamped or formed sections secured together to form the strut with a compound curvature includes a neck that has a bore to receive a hub of the barrel. The end cap has a pitot port for sensing fluid pressure. The barrel includes a water trap at its leading end for trapping water and permitting it to drain through a hole in the conical end cap. The longitudinal internal passageyway carries the fluid pressure sensed by the pitot port to remote instruments. The individual components are easily formed and are secured together to make the pitot pressure sensing probe assembly.

An arithmetic processing method and system in a wide velocity range flight velocity vector measurement system using a square truncated pyramid-shape five-hole Pitot probe. Approximation equations that determine attack angle alpha and sideslip angle beta in the form of third-order equations concerning attack angle pressure coefficient Calpha and sideslip angle pressure coefficient Cbeta, which are known numbers, are expressed in the form of a polynomial equation concerning Mach number M, where the coefficients are obtained from a lookup table. Coefficient calculations in the polynomial equation, and attack angle a and sideslip angle beta, calculations may be performed as simple calculations by specifying and applying known numbers into the approximation equation without solving third-order equations, with calibration coefficients that form the basis of coefficient calculation with the polynomial equation first being stored in memory in advance as a table for each wide velocity range on the basis of wind tunnel testing. A Mach number may be calculated instantly from a lookup table by specifying Mach pressure coefficient CM and angle to airflow pressure coefficient Cgamma. Wide velocity range flight velocity vector measurement with a high update rate which is capable of real time response in flight control as demanded by aircraft is obtained.

A system and method are provided for calculating Mach number and true airspeed without reference to data from a pitot static sensor. The true airspeed and Mach number are calculated using the altitude information from GPS, IRS, Radio Altimeter and other onboard sensors other than the air data computer (ADC). The computed true airspeed or Mach number could be used to confirm the ADC information or in lieu of the ADC information when the ADC information is unreliable or unavailable.

A method for yaw control for a wind turbine comprising a rotor with a rotor blade, the rotor defining a rotor axis and a rotor plane to which the rotor axis is perpendicular, in which the rotor axis is turned to minimise the yaw angle between the ambient wind direction and the rotor axis is provided, wherein the turning of the rotor axis is performed based on the measurement of a wind speed in the rotor plane at the rotor blade. Furthermore, a wind turbine which comprises a rotor which includes a rotor axis and a rotor plane perpendicular to the rotor axis and an anemometer for measuring the ambient wind speed is provided. The wind turbine further comprises an anemometer which is located such at a rotor blade at a particular distance from the rotor axis as to allow for measuring a wind speed in the rotor plane.

The invention provides a wind speed and direction real-time measuring method and a device of a high-altitude sky-parking aircraft. The method is composed of a measuring device and a wind speed and direction extraction algorithm, wherein, the measuring device is a rigid rotary rod which is driven by a brushless motor and rotates at a constant angular speed, two ends of the rigid rotary rod are provided with pressure measuring probes which are connected to a differential pressure transducer. When wind blows to the rigid rotary rod which constantly rotates, the pressure difference between the two pressure measuring probes is a periodic cosine signal, and the amplitude of the signal is in direct proportion to the wind speed, and the phase position of the signal contains wind angle information. By adopting the extraction algorithm of the invention, wind speed and direction information can be extracted from the differential pressure signal. The invention is characterized in that the amplitude of the differential pressure signal is in direct proportion to the product of atmospheric density and the linear speed of a rotary arm at the predetermined wind speed. Thus, in the invention, larger signal amount can be obtained under lower atmospheric density by reasonably selecting the rotating speed of the rigid rotary rod and the length of the rotary arm so as to reliably extract the wind speed and direction information.

The invention relates to wind speed and direction measurement technology, and aims to provide an anemoclinograph wind meter with high precision, good stability and low cost. The anemoclinograph wind meter comprises a wind measuring head and a signal processing device, wherein the wind measuring head consists of a shell, pull pressure sensors and a support bar; a horizontal circular section in the hollow shell is distributed with three pull pressure sensors with the same specification, which are symmetrically distributed at an interval of 120 degrees around a center of a circle; one end of each pull pressure sensor is fixed on the inner wall of the shell, while the other end is fixed on the support bar; the shell is not contacted with the support bar; wind pressure born by the shell is gathered on the support bar through the sensors, so the resultant force of the pull pressure of the sensors corresponds to the wind pressure; and the pressure direction indicates the wind direction, and the pressure and the wind speed have a certain functional relation which depends on the shape and size of the shell and can be calculated through a fluid mechanics theory or obtained through wind tunnel tests. The anemoclinograph wind meter can be used for wind generating systems, and also can be applied to the fields such as meteorology, transportation and the like.

An optical anemometric probe includes a laser source emitting a linearly polarized primary light beam and an optical block having splitting means for separating the primary beam, an optical reference pathway, an optical emission pathway and an optical measurement pathway. The optical block includes optical means of rotation of the polarization arranged at the output of the laser source and before the splitting means. The optical emission pathway has an optical circulator, a first optical emission/reception head illuminating a first measurement zone, and a second optical emission/reception head illuminating a second measurement zone. The optical circulator has four ports, e.g., a first input port, a second and a third input/ouput port linked respectively to the first optical head and to the second optical head, and a fourth port linked to the optical measurement pathway.

A total air temperature sensor probe samples the air stream surrounding an aircraft in flight, and includes a duct carrying a fluid flow a portion of which is diverted to a primary chamber mounting a total air temperature sensor. A secondary chamber has a secondary sensor for sensing a different property of a sampled air stream. The secondary chamber is open to receive air flow from passageways in the total air temperature probe.

The invention relates to the technical field of aviation. The inventive air data measuring system comprises a pitot pressure probe provided with sensing ports, an anti-freezing electric heater, a conduit, a pressure transducer, an outdoor air temperature sensor and an onboard computer; all the devices and parts are fixed in a streamlined housing attached to an aircraft and composed of an axial symmetric plane; the measuring system acquiring air data can be controlled automatically and interacts with the aircraft and other subsystems by electric connectors through an information interchange channel and power cords. In order to provide the system with more automation, the housing also comprises a power supply adapter. In order to extend the measuring range, reduce the structure weight and the required number of pressure measuring channels, the system comprises a pitot pressure probe which extends out convexly from the housing, is in a shape of small needle and is provided with sensing ports between the edges. In order to reduce the power required by the anti-freezing system and to simplify the structure design, the housing surface or a part thereof can be made of a hydrophobic material. In order to extend flight parameter measuring range, when the attack angle and the sideslip angle is -180 to 180 degrees, the whole range is covered.

A system and method are provided for calculating Mach number and true airspeed without reference to data from a pitot static sensor. The true airspeed and Mach number are calculated using the altitude information from GPS, IRS, Radio Altimeter and other onboard sensors other than the air data computer (ADC). The computed true airspeed or Mach number could be used to confirm the ADC information or in lieu of the ADC information when the ADC information is unreliable or unavailable.

A method and apparatus for detecting a fault in a sensor for an air data system which uses artificial intelligence to generate air data parameters is disclosed. The method and apparatus generate air data parameters as a function of measured values such as static pressures. The system also generates a fault detection value based upon the received value. The fault detection value is then input into a second network having artificial intelligence to determine if a sensor has experienced a fault.

A system for calculating airspeed and dynamic pressure comprises a system body, an internal accelerometer, located within the system body, an internal pressure sensor, located in the system body, the internal pressure sensor being not hermetically sealed within the system body and capable of measuring the static pressure of the ambient atmosphere, and a processor in reception of the internal accelerometer, and the internal pressure sensor, capable of calculating Mach number via an axial acceleration, and capable of calculating a dynamic pressure and a true airspeed via the Mach number.

Systems and methods for feedback protection of pressure measurement devices are disclosed. In one embodiment, a transmitter inside a pressure measurement device transmits a transmission signal directly or indirectly toward an ambient opening of the pressure measurement device. A reflection of the transmission signal is then received at a receiver and data associated with the transmission signal and the reflection of the transmission signal are examined to determine if an obstruction exists in the pressure measurement device.

Method and device for detecting an erroneous speed generated by an air data inertial reference system. The device (1) comprises means (2) for detecting an erroneous speed provided by an air data and inertial data system (3) and means for generating a substitution speed.

The invention discloses a system for measuring the flow rate of debris flow, a measuring method and an application thereof. The invention provides the measuring system against the problem that the prior art can not effectively measure the internal flow rate of the debris flow, the measuring system comprises a measuring device, a data collection device and a data processing device which are sequentially connected, wherein the measuring device comprises at least one impact sensor and at least one hydrostatic pressure sensor, the force receiving surface of the impact sensor is vertical to the flow direction of the debris flow; the force bearing surface of the hydrostatic pressure sensor is parallel to the flow direction of the debris flow; and the impact sensor and the hydrostatic pressure sensor which are positioned at the same horizontal height are used for measuring the original impact and the hydrostatic pressure of slurry of the debris flow at the horizontal height respectively. The measuring method provided by the invention can calculate according to data obtained by the measuring system, thereby obtaining the internal flow rate of the debris flow. The measuring system has simple structure, the measuring method has reliable principles, easy operation and high accuracy of measurement result, and the measuring system and the measuring method can be used in the flow rate measurement of the debris flow in field prototypes and indoor tests.

The invention discloses a method for testing droplets in smoke, which comprises firstly, setting a droplets sampling system, secondly, testing and calculating smoke flowing speed through an L-shape pitot tube (11), thirdly, adjusting airflow controlling valve (9a) which is on a vacuum pump of the droplets sampling system according to the testing smoke flowing speed. Droplets density can be calculated according to the quality of the droplets which are collected by a droplets collecting device. The invention adopts a constant velocity aspirating smoke method, the droplets in the smoke are collected by the droplets collecting device, droplet quality can be obtained through weighing weights of the droplets collecting device before and after collecting, and furthermore the droplets density can be obtained through formulas. Compared with a traditional method, the method needs no precise equipment tests as atomic absorption spectrometry, thereby testing data is minimized, the operation is easier, and testing results are more accurate.

It is an object of the present invention to solve the problem of a drop in precision in conventional systems using a square pyramid type five-hole probe due to the drop in atmospheric pressure in high altitude ranges, and to provide a wide velocity range flight velocity vector measurement system that can prevent a drop in measurement precision. Furthermore, it is also an object of the present invention to provide a method for eliminating the effects of detection fluctuations caused by adhering water droplets, ice particles or dust in a wide velocity range flight velocity vector measurement system. The flight velocity vector measurement probe of the present invention comprises means in which a static pressure hole is formed in the tube wall surface of the probe, so that a static pressure value is obtained from the pressure detected by this static pressure hole, the Mach number M is calculated on the basis of an equation approximated by a fourth-order polynomial of the static pressure/total pressure signal and the angle of attack, and in cases where an abnormal detection value is detected, this is replaced by the preceding detection value.

Sensors for air flow, temperature, pressure, and humidity are integrated onto a single semiconductor die within a miniaturized Venturi chamber to provide a microelectronic semiconductor-based environmental multi-sensor module that includes an air flow meter. One or more such multi-sensor modules can be used as building blocks in dedicated application-specific integrated circuits (ASICs) for use in environmental control appliances that rely on measurements of air flow. Furthermore, the sensor module can be built on top of existing circuitry that can be used to process signals from the sensors. By integrating the Venturi chamber with accompanying environmental sensors, correction factors can be obtained and applied to compensate for temporal humidity fluctuations and spatial temperature variation using the Venturi apparatus.

Embodiments of a method to determine airspeed for aircraft include determining critical air data parameters without the use of pitot-static systems. Airspeed may be determined by iteratively repeating the method until converging on a stable airspeed value that differs from a previous airspeed value by less than a predetermined threshold. Airspeed may be determined by modeling aircraft lift and repeatedly updating dynamic pressure to converge on an airspeed based on the balance between aircraft lift and weight. Airspeed may be determined based on predetermined relationships between a horizontal control surface position and dynamic pressure. A voting logic method validates or invalidates airspeeds from dissimilar sources, including airspeeds determined using the methods described herein and conventional pitot-static systems.

Methods and apparatus enable sensing flow of a fluid inside a conduit with an array of pressure or strain sensors. Inputs for a curve fit routine include power correlation values at one of multiple trial velocities or speeds of sound and several steps on either side utilizing data obtained from the sensors. The velocity at which a curve fit routine returns a max curvature result corresponds to an estimate value that facilitates identification of a speed of sound in the fluid and/or a velocity of the flow. Furthermore, a directional quality compensation factor may apply to outputs from the curve fit routine to additionally aid in determining the velocity of the flow.