A physical quantity measurement device includes a housing forming a measurement flow path in which a sensor support supports a physical quantity sensor. The measurement flow path includes a sensor path in which the physical quantity sensor is disposed, an upstream curved path between the sensor path and an inlet, and a downstream curved path between the sensor path and an outlet. The housing includes a measurement narrowed portion that gradually narrows the measurement flow path in a direction from the inlet toward the physical quantity sensor. An upstream end of the sensor support is provided upstream of the measurement narrowed portion in an arrangement cross section along an imaginary straight line passing through the physical quantity sensor and extending in an arrangement direction in which the upstream curved path and the downstream curved path are arranged.

A method for determining a flow rate and/or a flow velocity of a medium interacting with at least a first and a second temperature sensor element and a heating element, wherein the method comprises the following method steps: heating the medium by means of the heating element for a predetermined heating duration, wherein the medium before the heating is largely in thermal equilibrium with at least the first and second temperature sensor elements; registering at least a first and a second measured value with the assistance of the first temperature sensor element and at least a third and a fourth measured value with the assistance of the second temperature sensor element for characterizing first and second temperature rises of the medium; and ascertaining the flow rate and/or flow velocity of the medium based on the at least two temperature rises.

A method for determining a flow rate and/or a flow velocity of a medium interacting with at least a first and a second temperature sensor element and a heating element, wherein the method comprises the following method steps: heating the medium by means of the heating element for a predetermined heating duration, wherein the medium before the heating is largely in thermal equilibrium with at least the first and second temperature sensor elements; registering at least a first and a second measured value with the assistance of the first temperature sensor element and at least a third and a fourth measured value with the assistance of the second temperature sensor element for characterizing first and second temperature rises of the medium; and ascertaining the flow rate and/or flow velocity of the medium based on the at least two temperature rises.

A processing unit processes a signal output from a sensor unit that outputs a signal corresponding to an intake air amount that is an amount of intake air flowing through an intake flow path of an internal combustion engine. The processing unit has an advance processing section and a smoothing processing section. The advance processing section performs an advance process on the signal output from the sensor unit to compensate for a response delay. The smoothing processing section performs a smoothing process on the signal processed by the advance processing section.

The present disclosure provides a method for predicting a fluid type, comprising sensing, by a first sensor, mass flow data of a fluid in an engine, wherein the first sensor operates based on a first fluid property; sensing, by a second sensor, mass flow data of the fluid, wherein the second sensor operates based on a second fluid property; and detecting, by a logic circuit of a controller, a percent difference in the mass flow data provided by the first and second sensors, the percent difference indicating that the fluid is comprised of at least a first fluid type.

The present disclosure provides a method for predicting a fluid type, comprising sensing, by a first sensor, mass flow data of a fluid in an engine, wherein the first sensor operates based on a first fluid property; sensing, by a second sensor, mass flow data of the fluid, wherein the second sensor operates based on a second fluid property; and detecting, by a logic circuit of a controller, a percent difference in the mass flow data provided by the first and second sensors, the percent difference indicating that the fluid is comprised of at least a first fluid type.

A flow sensor configured to detect a fluid flow of a liquid inside a pipe portion is disclosed. A thin film thermal mass flow sensor has a substrate defining a thickness from an upper side opposite a bottom side. The upper side of the substrate supports a resistive heating circuit, a first temperature sensor circuit and a second temperature sensor circuit. The resistive heating circuit is disposed between the first and second temperature sensor circuits. The circuits are electrically connected respectively to a plurality of leadwires configured to be attachable to electronic equipment. A thermally conductive membrane is configured to separate the fluid flow of the liquid inside the pipe portion from the thin film thermal mass flow sensor. A thermally conductive bond connects the bottom side of the substrate of the thin film thermal mass flow sensor to the thermally conductive membrane.

A flow sensor configured to detect a fluid flow of a liquid inside a pipe portion is disclosed. A thin film thermal mass flow sensor has a substrate defining a thickness from an upper side opposite a bottom side. The upper side of the substrate supports a resistive heating circuit, a first temperature sensor circuit and a second temperature sensor circuit. The resistive heating circuit is disposed between the first and second temperature sensor circuits. The circuits are electrically connected respectively to a plurality of leadwires configured to be attachable to electronic equipment. A thermally conductive membrane is configured to separate the fluid flow of the liquid inside the pipe portion from the thin film thermal mass flow sensor. A thermally conductive bond connects the bottom side of the substrate of the thin film thermal mass flow sensor to the thermally conductive membrane.

A sensor device according to the present invention includes a substrate including a heat generation portion, a casing including an accommodation portion accommodating the substrate, and a sensor element including a temperature-sensitive resistor and being supported by the substrate, in which the accommodation portion is divided into a plurality of accommodation spaces on a side closer to the sensor element. The accommodation portion is divided into a first accommodation space and a second accommodation space via division plates, and the first accommodation space is formed on a side closer to the sensor element than the second accommodation space, and widely as compared with the second accommodation space.

A sensor device according to the present invention includes a substrate including a heat generation portion, a casing including an accommodation portion accommodating the substrate, and a sensor element including a temperature-sensitive resistor and being supported by the substrate, in which the accommodation portion is divided into a plurality of accommodation spaces on a side closer to the sensor element. The accommodation portion is divided into a first accommodation space and a second accommodation space via division plates, and the first accommodation space is formed on a side closer to the sensor element than the second accommodation space, and widely as compared with the second accommodation space.