A physical quantity measurement device that measures a physical quantity of a fluid has an inflow port and an outflow port, and includes a passage flow channel, a branch flow channel, and a physical quantity detector. An inner peripheral surface of the passage flow channel extends over a pair of facing surfaces, which face each other across the flow passage boundary portion and the inflow port on an upstream side of the flow channel boundary portion. The inner peripheral surface further includes an inflow step surface which forms a step facing the inflow port side.

A physical quantity measurement device that measures a physical quantity of a fluid has an inflow port and an outflow port, and includes a passage flow channel, a branch flow channel, and a physical quantity detector. An inner peripheral surface of the passage flow channel extends over a pair of facing surfaces, which face each other across the flow passage boundary portion and the inflow port on an upstream side of the flow channel boundary portion. The inner peripheral surface further includes an inflow step surface which forms a step facing the inflow port side.

A method for operating a thermal flow sensor includes: bringing a measuring medium into thermal contact with a sensor element of the flow sensor and periodically heating the medium using an AC voltage introduced into the sensor element; simultaneously detecting a maximum amplitude of a temperature and/or a phase shift between a curve of the AC voltage and the curve of the temperature; adjusting the detected maximum amplitude and/or the detected phase shift using calibration data; determining an isoline using the adjusted maximum amplitude and/or the adjusted phase shift based on model of the flow sensor, wherein the isoline has a plurality of value pairs of thermal conductivity and thermal capacitance of the medium; deriving a medium information from the isoline; and performing a flow measurement by converting signal values from the sensor element into measurement values of an effective flow velocity of the medium using the medium information.

The present invention provides a thermal flow meter that includes a sensor flow path along which flows a fluid being measured, an upstream-side electrical resistance element provided on the sensor flow path, a downstream-side electrical resistance element provided downstream of the upstream-side electrical resistance element, a sensor output generator that, based on respective voltages that are output in accordance with changes in the upstream-side and downstream-side electrical resistance elements, generates a sensor output in accordance with the flow rate of the fluid being measured, a slope effect estimator that, based on at least a Prandtl number of the fluid being measured, estimates a slope effect that is generated in the sensor output in accordance with an attitude of the sensor flow path, and a flow rate calculator that corrects the slope effect from the sensor output, and calculates the flow rate of the fluid being measured.

A device which: optically detects the presence of, measures the flow rate of, and identifies the characteristics of venting fugitive gas emissions. Specifically the device provides a spectral analysis of emission gas constituents; selective detection of the presence of venting hydrocarbons; measurement of venting emissions flow rates, the measurement of shut-in and flowing venting system pressures and the venting system temperatures. The flow rates are corrected, relative to the detection of the gas constituents and standard temperature and pressure (STP). These devices are configured to collect such data electronically and transmit via various telemetry systems, to a secure remote data network for reporting, access, evaluation, real-time monitoring and archiving as required.

A method is provided for measuring different flow properties of a fluid. The method includes (a) providing a nanowire, the resistance of the nanowire varying based on temperature changes of the nanowire that reflect values of the different flow properties of the fluid when the nanowire is operated in different modes of operation respectively, such that the nanowire measures different flow properties when operated in different modes of operation respectively, and (b) alternating the nanowire between different modes of operation, measuring different flow properties of the fluid during the different modes of operation, respectively, and using the measurements of one of the flow properties to correct the measurements of another flow property. Other applications are also described.

A method is provided for measuring different flow properties of a fluid. The method includes (a) providing a nanowire, the resistance of the nanowire varying based on temperature changes of the nanowire that reflect values of the different flow properties of the fluid when the nanowire is operated in different modes of operation respectively, such that the nanowire measures different flow properties when operated in different modes of operation respectively, and (b) alternating the nanowire between different modes of operation, measuring different flow properties of the fluid during the different modes of operation, respectively, and using the measurements of one of the flow properties to correct the measurements of another flow property. Other applications are also described.

According to one embodiment, a sensor includes a detector. The detector includes a first resistance member, a second resistance member, a third resistance member, and a conductive member. A position of the third resistance member in a first direction from the first resistance member to the second resistance member is between a position of the first resistance member in the first direction and a position of the second resistance member in the first direction. A second direction from the conductive member to the third resistance member crosses the first direction. A third electrical resistance of the third resistance member is configured to change depending on a target substance around the detector.

According to one embodiment, a sensor includes a detector. The detector includes a first resistance member, a second resistance member, a third resistance member, and a conductive member. A position of the third resistance member in a first direction from the first resistance member to the second resistance member is between a position of the first resistance member in the first direction and a position of the second resistance member in the first direction. A second direction from the conductive member to the third resistance member crosses the first direction. A third electrical resistance of the third resistance member is configured to change depending on a target substance around the detector.

Methods, systems, and apparatuses are provided for detecting and determining conditions of and conditions within a fluid conduit.