A fluid flow device that can measure and control a flow of a fluid is described. Various procedures, including measuring, controlling, balancing, or calibration procedures can leverage differential pressure measurement. These differential pressure measurements can be measured across the fluid flow device such that a first pressure measurement is taken upstream of the fluid flow device while a second pressure measurement is taken downstream of the fluid flow device. Moreover, one or more of the various pressure measurements, and in particular the downstream pressure measurement, can be performed at stagnation zone where the flow has stagnated. Such can provide significant amplification and/or turndown capabilities.

A differential MEMS pressure sensor includes a topping wafer with a top side and a bottom side, a diaphragm wafer having a top side connected to the bottom side of the topping wafer and a bottom side, and a backing wafer having a top side connected to the bottom side of the diaphragm wafer and a bottom side. The topping wafer includes a first cavity formed in the bottom side of the topping wafer. The diaphragm wafer includes a diaphragm, a second cavity formed in the bottom side of the diaphragm wafer underneath the diaphragm, an outer portion surrounding the diaphragm, and a trench formed in the top side of the diaphragm wafer and positioned in the outer portion surrounding the diaphragm.

A differential MEMS pressure sensor includes a topping wafer with a top side and a bottom side, a diaphragm wafer having a top side connected to the bottom side of the topping wafer and a bottom side, and a backing wafer having a top side connected to the bottom side of the diaphragm wafer and a bottom side. The topping wafer includes a first cavity formed in the bottom side of the topping wafer. The diaphragm wafer includes a diaphragm, a second cavity formed in the bottom side of the diaphragm wafer underneath the diaphragm, an outer portion surrounding the diaphragm, and a trench formed in the top side of the diaphragm wafer and positioned in the outer portion surrounding the diaphragm.

A device and method for measuring a volume of liquid expelled from a syringe is provided. The device generally includes a syringe barrel, a plunger actuated with a plunger rod, and a sensor. The sensor may include two ports with one port being in fluid communication with a source of fluid external to the syringe barrel, while the second port is in fluid communication either with a proximal end portion of the syringe barrel or a hollow plunger rod having a first end closed by the plunger. The method may include expelling liquid from the syringe; detecting and recording differential pressure with the sensor over time; and calculating the volume of liquid expelled from the syringe from the recorded differential pressure over time.

A device and method for measuring a volume of liquid expelled from a syringe is provided. The device generally includes a syringe barrel, a plunger actuated with a plunger rod, and a sensor. The sensor may include two ports with one port being in fluid communication with a source of fluid external to the syringe barrel, while the second port is in fluid communication either with a proximal end portion of the syringe barrel or a hollow plunger rod having a first end closed by the plunger. The method may include expelling liquid from the syringe; detecting and recording differential pressure with the sensor over time; and calculating the volume of liquid expelled from the syringe from the recorded differential pressure over time.

To make it possible to incorporate a fluid resistance element into a flow path through which a fluid flows without difficulty while enjoying advantages from forming a resistance flow path using ceramic, provided is a fluid resistance element including: a ceramic flow path forming member having one or a plurality of resistance flow paths; and a metal covering member covering an outer peripheral face of the flow path forming member.

In order to prevent unnatural behavior of a calculated flow rate, provided is a fluid control device in which a fluid control valve and upstream and downstream pressure sensors are provided on a flow path. The device includes a calculation unit configured to calculate a flow rate based on measured pressures; and an output unit configured to output the calculated flow rate, and exhibit a zero output function of outputting a zero value regardless of the calculated flow rate when the valve is in a closed state. The device is further configured to switch between execution and stop of the zero output function, and when the valve is in an open state and a difference between the measured pressures of the pressure sensors is larger than a threshold, stop the zero output function and cause the flow rate output unit to output the calculated flow rate.

In order to prevent unnatural behavior of a calculated flow rate, provided is a fluid control device in which a fluid control valve and upstream and downstream pressure sensors are provided on a flow path. The device includes a calculation unit configured to calculate a flow rate based on measured pressures; and an output unit configured to output the calculated flow rate, and exhibit a zero output function of outputting a zero value regardless of the calculated flow rate when the valve is in a closed state. The device is further configured to switch between execution and stop of the zero output function, and when the valve is in an open state and a difference between the measured pressures of the pressure sensors is larger than a threshold, stop the zero output function and cause the flow rate output unit to output the calculated flow rate.

A system for measuring a velocity or volumetric fluid flow rate of a fluid flow passing within a pipe includes a SONAR flow meter configured to determine a measured velocity or volumetric rate of a fluid flow passing within a pipe. The system further includes a CFD analysis device configured to produce a simulated velocity or volumetric rate of the fluid flow passing within the pipe. The system further includes a processing unit in communication with the CFD analysis device and the SONAR flow meter. The processing unit is configured to produce at least one error function based on the measured velocity or volumetric fluid flow rate and the simulated velocity or volumetric fluid flow rate, and is configured to determine an adjusted velocity or volumetric fluid flow rate using the at least one error function and the measured velocity or volumetric fluid flow rate.

A system for measuring a velocity or volumetric fluid flow rate of a fluid flow passing within a pipe includes a SONAR flow meter configured to determine a measured velocity or volumetric rate of a fluid flow passing within a pipe. The system further includes a CFD analysis device configured to produce a simulated velocity or volumetric rate of the fluid flow passing within the pipe. The system further includes a processing unit in communication with the CFD analysis device and the SONAR flow meter. The processing unit is configured to produce at least one error function based on the measured velocity or volumetric fluid flow rate and the simulated velocity or volumetric fluid flow rate, and is configured to determine an adjusted velocity or volumetric fluid flow rate using the at least one error function and the measured velocity or volumetric fluid flow rate.