A measuring device for determining density, mass flow rate and/or viscosity of a flowable medium includes: an oscillator including at least one oscillatable measuring tube for conveying the medium, and having at least one oscillatory mode, whose eigenfrequency depends on density of the medium; an exciter for exciting the oscillatory mode; at least one oscillation sensor for registering oscillations of the oscillator; and an operating-evaluating circuit, which is adapted to supply the exciter with an excitation signal, to register signals of the oscillation sensor, based on the signals of the oscillation sensor to ascertain current values of the eigenfrequency of the oscillator as well as variations of the eigenfrequency, and to determine a value characterizing density variations of the medium, wherein the value depends on a function, which is proportional to the variation of the eigenfrequency and has an eigenfrequency dependent normalization.

A Coriolis measuring sensor of a Coriolis measuring device includes: at least a pair of measuring tubes; a support body; at least one exciter; and at least two electromagnetic sensors per pair of measuring tubes, wherein the electromagnetic sensors are configured to mask interference magnetic fields and to detect local inhomogeneous magnetic fields generated by magnet devices of the sensor according to a winding direction and/or an interconnection configuration of coils of the magnet devices.

In accordance with example embodiments of the present disclosure, a method for determining parameters for, and application of, models that correct for the effects of fluid inhomogeniety and compressibility on the ability of Coriolis meters to accurately measure the mass flow and/or density of a process fluid on a continuous basis is disclosed. Example embodiments mitigate the effect of multiphase fluid conditions on a Coriolis meter.

A method for correcting a measured value of a measured variable with reference to a medium flowing through at least two measuring tubes, wherein each measuring tube is excited by an oscillation exciter to execute oscillations, and wherein the oscillations of each measuring tube are registered by oscillation sensors, wherein an electronic circuit monitors at least two of the following measured variables or, in each case, a measured variable derived therefrom: phase difference between measurement signals, resonant frequency, ratio of an oscillation exciter electrical current amplitude to a measuring tube oscillation amplitude, the method including: determining a plausibility; and, wherein upon failing a plausibility requirement of at least one of the measured variables, determining measured values of the measured variables of at least one, first/second measuring tube as a function of corresponding measured values of the measured variables of at least one, second/first measurement tube.

A mass flow controller assembly includes a housing defining a cavity, a plurality of internal passages, a first inlet, a first outlet, a second inlet, and a second outlet. A valve is connected to the housing, has an inlet fluidly coupled to the second outlet of the housing and an outlet fluidly coupled to the second inlet of the housing. The valve is configured to control fluid flow from the second outlet of the housing to the second inlet of the housing. A microelectromechanical (MEMS) Coriolis flow sensor is arranged in the cavity, includes an inlet fluidly coupled by at least one of the plurality of internal passages to the first inlet of the housing and is configured to measure at least one of a mass flow rate and density of fluid flowing through the MEMS Coriolis flow sensor. An outlet of the MEMS Coriolis flow sensor is fluidly coupled by at least one of the plurality of internal passages to the second outlet of the housing. The second inlet of the housing is fluidly coupled by at least one of the plurality of internal passages to the first outlet of the housing.

A fluid delivery system includes N first valves. Inlets of the N first valves are fluidly connected to N gas sources, respectively, where N is an integer greater than zero. N mass flow controllers include a microelectromechanical (MEMS) Coriolis flow sensor having an inlet in fluid communication with an outlet of a corresponding one of the N first valves. A second valve has an inlet in fluid communication with an outlet of the MEMS Coriolis flow sensor and an outlet supplying fluid to treat a substrate arranged in a processing chamber. A controller in communication with the MEMS Coriolis flow sensor is configured to determine at least one of a mass flow rate and a density of fluid flowing through the MEMS Coriolis flow sensor.

A method for determining the gas portion in the medium flowing through a Coriolis mass flowmeter, wherein the Coriolis mass flowmeter has at least one measuring tube, at least one oscillation generator, at least two oscillation sensors and at least one control and evaluation unit, wherein the method is characterized in that the density value ρ.sub.100 of the gas-free medium is determined in a ρ.sub.100 step, that the density value ρ.sub.mess of the medium flowing through the measuring tube is measured in a ρ.sub.mess step, that a quantity GVQ for the gas portion of the medium flowing through the measuring tube is calculated in a GVQ step with the density value ρ.sub.100 and the density value ρ.sub.mess, and that the quantity GVQ is output for the gas portion of the medium flowing through the measuring tube.

A coriolis mass flow meter, including: a housing body, having a flow inlet and flow outlet for a fluid medium, two measurement tubes, which are spaced apart from each other fastened to the housing body connecting the flow inlet and the flow outlet to each other, at least one electrically controllable vibration exciter for each measurement tube (23, 24), the vibration exciter being designed to cause the measurement tube to vibrate, and at least two electrically controllable vibration sensors, the vibration sensors being designed to sense the vibration of at least one of the two measurement tubes. The vibration exciter vibration sensors are spatially fixedly fastened to the housing body between the two measurement tubes and are designed as electromagnetic coils. Each coil interacts with a permanent magnet fastened to one of the measurement tubes. The permanent magnets are oriented in such a way that permanent magnets attract each other.

A Coriolis measuring device for measuring volume flow or density of a medium flowing through a measuring tube is disclosed, the device comprising: the measuring tube for conveying the medium; at least one exciter, which is adapted to excite the measuring tube to execute oscillations; at least one sensor, which is adapted to register the oscillations of the measuring tube; an electronic measuring/operating circuit, which is adapted to operate the exciter as well as the sensor and to determine and to output flow and/or density measurement values; wherein the electronic measuring/operating circuit has an electronics board, wherein at least one exciter has a stationary exciter element, and/or wherein at least one sensor has a stationary sensor element, wherein at least one stationary exciter element and/or at least one stationary sensor element is integrated into the electronics board.

A mass flow controller assembly includes a housing defining a cavity, a plurality of internal passages, a first inlet, a first outlet, a second inlet, and a second outlet. A valve is connected to the housing, has an inlet fluidly coupled to the second outlet of the housing and an outlet fluidly coupled to the second inlet of the housing. The valve is configured to control fluid flow from the second outlet of the housing to the second inlet of the housing. A microelectromechanical (MEMS) Coriolis flow sensor is arranged in the cavity, includes an inlet fluidly coupled by at least one of the plurality of internal passages to the first inlet of the housing and is configured to measure at least one of a mass flow rate and density of fluid flowing through the MEMS Coriolis flow sensor. An outlet of the MEMS Coriolis flow sensor is fluidly coupled by at least one of the plurality of internal passages to the second outlet of the housing. The second inlet of the housing is fluidly coupled by at least one of the plurality of internal passages to the first outlet of the housing.