Proposed is a flow sensor (10), in particular for single use, having at least three measurement chambers (11, 15, 19), which are arranged one behind the other and are interconnected in each case by a flow resistance. At least two of the flow resistances have a different coefficient of pressure loss. A pressure measuring means (12, 16, 20) is provided for each measurement chamber, which pressure measuring means (12, 16, 20) is suitable for measuring the pressure in the measurement chamber. An electromagnetically actuatable valve arrangement (50) can be connected downstream of the flow sensor.

Proposed is a flow sensor (10), in particular for single use, having at least three measurement chambers (11, 15, 19), which are arranged one behind the other and are interconnected in each case by a flow resistance. At least two of the flow resistances have a different coefficient of pressure loss. A pressure measuring means (12, 16, 20) is provided for each measurement chamber, which pressure measuring means (12, 16, 20) is suitable for measuring the pressure in the measurement chamber. An electromagnetically actuatable valve arrangement (50) can be connected downstream of the flow sensor.

A method for calibrating a product valve disposed along a flow path in a duct, with a calibration valve in a duct remote from the product valve and having a geometric shape and operational parameters corresponding to those of the product valve. A calibration controller establishes calibration conditions and, in responsive thereto, generates a calibration flow rate (CFM) function by measuring for the calibration valve, a sparse set of flow rates and determining a surface-fit mathematical representation of fluid flow through the calibration valve over applied calibrated flow rates and the measured pressure drops. The CFM Function is transferred to a product blade controller, which in turn, processes the representation of the mathematical surface, and controls fluid flow through product valve based on values extracted from the received CFM Function as well as at least one parameter control signal indicative of a desired set point.

A method for calibrating a product valve disposed along a flow path in a duct, with a calibration valve in a duct remote from the product valve and having a geometric shape and operational parameters corresponding to those of the product valve. A calibration controller establishes calibration conditions and, in responsive thereto, generates a calibration flow rate (CFM) function by measuring for the calibration valve, a sparse set of flow rates and determining a surface-fit mathematical representation of fluid flow through the calibration valve over applied calibrated flow rates and the measured pressure drops. The CFM Function is transferred to a product blade controller, which in turn, processes the representation of the mathematical surface, and controls fluid flow through product valve based on values extracted from the received CFM Function as well as at least one parameter control signal indicative of a desired set point.

A measurement carrier includes a housing having an internal space, and a flow-rate measuring device located within the internal space. A bottom surface of the housing includes a first inflow hole, a second inflow hole, and an outflow hole, which provide fluid communication between the internal space and an outer space. The flow-rate measuring device may include a first flow-rate measuring sensor in fluid communication with the first inflow hole, and a second flow-rate measuring sensor in fluid communication with the second inflow hole.

A measurement carrier includes a housing having an internal space, and a flow-rate measuring device located within the internal space. A bottom surface of the housing includes a first inflow hole, a second inflow hole, and an outflow hole, which provide fluid communication between the internal space and an outer space. The flow-rate measuring device may include a first flow-rate measuring sensor in fluid communication with the first inflow hole, and a second flow-rate measuring sensor in fluid communication with the second inflow hole.

Provided are systems and methods for accurate sensing of particle concentrations in fluids by employing a particle impactor system that allows for collection, growth and analysis of biological particles. The disclosed systems and methods make use of a pressure based flow sensor which permits the particle impactor system systems to accurately and reliably provide measurements of biological particle concentrations in the ambient environment. By incorporation of pressure sensors and pressure measurements into the flow measurement techniques, embodiments provide for the ability to use a particle impactor system to accurately measure environmental biological particle concentrations at a variety of atmospheric pressure conditions, such as at high altitude or with minimal perturbation from atmospheric weather conditions, without requiring recalibration or other adjustment of the sensors and control systems.

Provided are systems and methods for accurate sensing of particle concentrations in fluids by employing a particle impactor system that allows for collection, growth and analysis of biological particles. The disclosed systems and methods make use of a pressure based flow sensor which permits the particle impactor system systems to accurately and reliably provide measurements of biological particle concentrations in the ambient environment. By incorporation of pressure sensors and pressure measurements into the flow measurement techniques, embodiments provide for the ability to use a particle impactor system to accurately measure environmental biological particle concentrations at a variety of atmospheric pressure conditions, such as at high altitude or with minimal perturbation from atmospheric weather conditions, without requiring recalibration or other adjustment of the sensors and control systems.

Storage units 60, 70 store a first computer program calculating a flow rate of an assist gas with a linear function having a pressure of the assist gas in a processing head 35 as a variable, and a second computer program calculating a slope of the linear function with a function having a gap G from a tip end of a nozzle 36 to a surface of a workpiece W as a variable. A control unit 50 substitutes a value of the gap G into the function to calculate the slope of the linear function and substitutes the slope of the linear function and a value of the pressure of the assist gas into the linear function to calculate the flow rate of the assist gas.

Storage units 60, 70 store a first computer program calculating a flow rate of an assist gas with a linear function having a pressure of the assist gas in a processing head 35 as a variable, and a second computer program calculating a slope of the linear function with a function having a gap G from a tip end of a nozzle 36 to a surface of a workpiece W as a variable. A control unit 50 substitutes a value of the gap G into the function to calculate the slope of the linear function and substitutes the slope of the linear function and a value of the pressure of the assist gas into the linear function to calculate the flow rate of the assist gas.