Abstract: The liquid and gas volumetric flow rates of a multiphase fluid mixture are measured by pumping the fluid mixture with a positive displacement pump such as a multi-helical lobed rotor type pump, measuring the pressure differential, temperature differential and power input to the pump and calculating the liquid volumetric flow rate and gas volumetric flow rate based on the measured parameters, pump coefficients for friction horse power, fluid leakage and heat transfer, together with predetermined values of liquid and gas specific heat, density and polytropic compression exponent. Approximate flow rates of gas and liquid may be determined by monitoring the pump power input and fluid pressure and temperature changes across the pump with sufficient accuracy for applications such as in pumping crude oil and natural gas mixtures from production wells.

Abstract: A coherent detection transceiver comprises a stack of semiconductor layers with an active layer (12) and a grating (16) having a phase shifter (18). An electrode (30) is placed above the phase shifter in order to tap a voltage. This voltage is processed in a heterodyne circuit (36) in order to restore the modulation of the light beam introduced into the active layer.

Abstract: A thermal air flow meter having therein a thermo sensitive film resistor and a charging current control circuit for controlling a current supplied to the thermo sensitive film resistor both being formed on a commom substrate by the same process technology, and the thermo sensitive film resistor unit being disposed along a direction of flow of an air to be detected.

Abstract: The flowrate of powder in an air-powder mixture circuit comprising a mixture drive area defined by a powder drive device comprising air injector means adapted to inject air in the direction in which the mixture is to be driven is measured by measuring the pressure difference across the drive area and the injected air flowrate and computing the powder flowrate as a function of these two variables. The degree of wear of a venturi tube which forms the drive area is calculated by integrating with respect to time two parameters representing air-powder mixture flow rate and the air flow rate.

Abstract: A rotary type of flowmeter having an orifice directing the flow toward a moveable needle. The needle moves within a channel that has a varying cross-sectional area in a plane transverse to the needle movement such that the effect of the velocity of the fluid impinging on the needle to cause its movement is controlled.

Abstract: A compound electronic filter for conditioning an alternating electrical signal generated by vortex shedding in a vortex flowmeter has a first stage filter comprising a first plurality of electronic filters respectively including a first plurality of electronic switches and a second stage filter comprising a second plurality of electronic filters respectively including a second plurality of electronic switches, wherein the first plurality of electronic switches switching on and off the first plurality of electronic filters one at a time are controlled by a first command signal generated from the frequency of the output signal from the first stage filter, and the second plurality of electronic switches switching on and off the second plurality of electronic filters one at a time are controlled by a second command signal generated from the frequency of the output signal from the first stage filter.

Abstract: A pressure differential flowmeter for respiratory flow measurement having enhanced signal processing. The non-linear nature of the signal generated by the differential pressure transducer is accommodated over a wide range of flows via a bank of amplifiers having differing gains, while baseline drift is compensated for by a combined analog and digital auto-referencing technique.

Abstract: A position sensor comprises a pair of elongated members of strip or tape shape having a high specific ohmic resistance, and a target member capacitively coupling two electric signals respectively flowing through the pair of elongated members, which target member is disposed in a relationship allowing sliding movements following the pair of elongated members, wherein the position of the target member relative to a reference section of the pair of elongated members is determined as a function of a phase angle difference between an alternating electrical signal supplied to one extremity of one of the pair of elongated members and another alternating electrical signal associated with the supplied electrical signal and taken off from one extremity of the other of the pair of elongated members.

Abstract: A temperature time-of-flight (TOF) sensor is combined with a nozzle of known flow area to create a TOF flowmeter. The TOF measured by the flow sensor provides a measure of gas volumetric flow rate. A TOF sensor has of a pulse heated wire and a single temperature sensor downstream of the wire. This single temperature sensor arrangement allows the accurate measurement of gas velocities much lower than the previously demonstrated limit of 0.3 m/s. The TOF sensor combined with a nozzle creates a new device such that the TOF measured with this device provides a measure of the gas flow rate rather than just the gas velocity. More than one nozzle in series is combined to achieve high flow measuring ranges. Compensation for variations in the thermophysical properties of the gas being metered is provided by pulsing the heated wire and measuring sensor outputs when both are immersed in the gas at zero velocity.

Abstract: A mass flowmeter has a flow tube inserted within the confines of a conduit containing a material flow. Mass flow information is derived for the material flow within the conduit by generating mass flow information for the material flowing within the smaller flow tube positioned within the conduit and then by adjusting the calculations for the flow tube to represent mass flow information for the conduit. In accordance with a first embodiment of the invention, a pressurized cover is positioned around the flow tube to isolate the exterior surface of the flow tube from the material in the conduit. The space between the exterior of the flow tube and the cover is pressurized to a pressure equal to that of the material in the conduit. Both sides of the flow tube walls are at the same pressure so that a flow tube comprised of thinner and more flexible material may be used.

Abstract: The portions on the sides far to each other of two sensor coils wound around the outer circumferential portion of the conduit, through which the fluid passes, at the suitable interval are thermally joined through a thermal conductor and the thermal conductor is heated by means of a heater, whereby the flow rate of fluid can be accurately measured without being influenced by the posture error resulting from the convection.

Abstract: A rigid central manifold block defines a coaxial inlet and outlet of the flowmeter and supports at least one continuous conduit loop substantially encircling the block and having its inlet and outlet ends closely spaced and rigidly connected to the block. Preferably, the loop includes a straight section perpendicular to the inlet and outlet ends. Dual drive means are preferably provided for oscillating the straight section back and forth about its perpendicular bisector and complementary position detectors employed at or near the opposite ends of the straight section, preferably at the same location as the drive units, provide readouts which are combined algebraically and synchronously demodulated to yield a Coriolis-related output indicative of mass flow. Preferably, a second loop, identical and parallel to the first, is supported by the same block. The block is channeled to serve as a manifold and interchangeable manifolds are disclosed for series and parallel flow through the two loops, respectively.

Abstract: A vortex flowmeter for measuring fluid flow includes a conduit having a wall surrounding a bore for carrying the fluid along a bore axis. A pivoting member moves in response to vortices in the fluid and extends from a hole in the wall into the bore, and sensing means is provided for sensing the motion of the pivoting member to provide a flow indicative output. In one embodiment, a torsional pin is disposed in the hole and couples to the pivoting member, and further has a first pin end attached to the wall. In another embodiment a diaphragm extending across the hole, together with the conduit wall and the pivoting member, are integrally formed from a material so as to present an unbroken overall surface to the fluid and to reduce crevices or gaps in which portions of the fluid can lodge. In another embodiment the pivoting member is at least a portion of a downstream extremity of a body disposed in the bore.

Abstract: A method and apparatus for measuring the gaseous flow of a fluid flowing along a duct, the apparatus comprises a processing and control unit connected firstly to a flow rate measuring device which delivers data representative of the flow rate Qm of the gas under the conditions of temperature Tm and pressure Pm that are determined by temperature and pressure sensors disposed in said duct, and secondly to a unit for determining the compressibility factor Zm, which unit delivers data representative of the dielectric constant .epsilon. of the gas flowing in the duct, so as to enable the flow rate Q of the gas to be determined as reduced to predefined reference conditions of temperature To, pressure Po, and compressibility factor Zo. The data representative of the dielectric constant of the gas is obtained by a capacitive transducer constituted by a cylindrical capacitor placed under the same thermodynamic conditions as applied to the flow of gas.

Abstract: An apparatus for detecting an intake air quantity for an internal, combustion engine and method therefor are disclosed in which a passed time from a time at which a power supply to a temperature sensitive airflow meter of a bridge circuit is turned on is measured as t. A CPU of the detecting apparatus retrieves a data on the intake air quantity from a data map storing the data on the intake air quantity, the passed time and output voltage of the temperature sensitive airflow meter to derive the intake air quantity data Q.sub.now. In addition, the CPU adds a value of a change rate of the present mapped data with respect to the previously derived final intake air quantity data Q.sub.-1 which is multiplied by a predetermined coefficient k to Q.sub.now. The result of addition is set as the present final intake air quantity data: Q.rarw.Q.sub.now +k (Q.sub.now -Q-.sub.-1). It is noted that the predetermined coefficient k is varied according to the passed time t.

Abstract: An improved water meter has a meter body with an extended bottom on the periphery of which are disposed a plurality of spaced first oval holes and at the center of the meter is disposed a small round hole. To the bottom of the water meter is journalled a cone-shaped block. A round cavity is disposed at the center of the block with a plurality of spaced first oval holes defined on the periphery thereof that communicate respectively with a plurality of tilted slots on the bottom periphery of the block. A vertical mounting post is disposed at the center of the cavity. A rotation propeller having a plurality of blades and a driving shaft is engaged with the small round hole with its driving shaft and engaged with the vertical mounting shaft at the bottom end. The cone-shaped block and the water meter are journalled together with the rotation propeller housed therebetween.

Abstract: A water meter housing has a scalloped edge positioned in a crevice where the housing attaches to a meter register housing to improve the tamper-resistant features of the assembly.

Abstract: A device for measuring a gas flow (F) has a measuring body (1) in the form of a cylinder, and a heating device (12) for heating the measuring body. A slot (5) extends axially into the cylinder from one end thereof so as to divide a first portion of the cylinder into two symmetrical halves (6a, 6b). The heating device (12) is disposed in a second cylinder portion which is not divided by the slot (5). A temperature sensor (13) is arranged in the second cylinder portion, and a temperature sensor (14, 15) is arranged in each cylinder half (6a, 6b). For measuring a gas flow (F), the measuring body (1) is so disposed in the gas flow that the slot (5) extends at right angles to the gas flow with one half (6a) facing the gas flow and with the other half (6b) facing away from the gas flow. The measuring body (1) is heated by the heating device (12) to a temperature exceeding the ambient temperature by a predetermined value.

Abstract: A positive-displacement fluid flow measuring system, especially for hydrocarbon fuel dispensers. The measuring system comprises, in addition to a positive-displacement meter per se, a correction system for correcting the loss of head in the meter. The correction system comprises a differential pressure detector responsive to the difference between the pressures at the inlet and the outlet of the meter. The displacement of the membrane enables an external motor to be coupled to the shaft of the meter by means of the plates.

Abstract: Elbow mass flow meter. The present invention includes a combination of an elbow pressure drop generator and a shunt-type mass flow sensor for providing an output which gives the mass flow rate of a gas that is nearly independent of the density of the gas. For air, the output is also approximately independent of humidity.