A flow measurement apparatus can include a main flow passage, a variable flow restrictor, a bypass flow passage having an inlet connected with the main flow passage upstream of the variable flow restrictor and an outlet connected with the main flow passage downstream of the variable flow restrictor, and a mass flowmeter connected in the bypass flow passage between the inlet and the outlet. A method can include connecting a flow measurement apparatus, so that a fluid flow in a well also flows through the flow measurement apparatus, and varying a restriction to the fluid flow through the variable flow restrictor in response to a change in a flow rate of the fluid flow.

Described herein are systems and devices for controlling and monitoring liquid applications of agricultural fields. In one embodiment, a flow device for controlling flow during an agricultural operation includes an offset ball valve having multiple openings that rotate in position to control flow of a liquid through the offset ball valve to an outlet passage. The flow device also includes a first passage that provides a first flow path from an inlet to at least one opening of the offset ball valve and second passage that provides a second flow path from the inlet to at least one opening of the offset ball valve.

Described herein are systems and devices for controlling and monitoring liquid applications of agricultural fields. In one embodiment, a flow device for controlling flow during an agricultural operation includes an offset ball valve having multiple openings that rotate in position to control flow of a liquid through the offset ball valve to an outlet passage. The flow device also includes a first passage that provides a first flow path from an inlet to at least one opening of the offset ball valve and second passage that provides a second flow path from the inlet to at least one opening of the offset ball valve.

Disclosed is a method for determining a flowed amount of a medium using a first flow measuring transducer according to a first measuring principle and a second flow measuring transducer according to a second measuring principle. The measured values of the first transducer are more reliable in first states of the medium than measured values of the second transducer, and the second measured values are more reliable in second states than the first measured values. A contribution to the flowed amount is ascertained based on the more reliable measured values. The contribution to the flowed amount based on the second measured values is ascertained by means of a transfer function. An updated version of the transfer function is ascertained when the first measured values are more reliable, and the flowed amount earlier ascertained based on the second measured values is corrected as a function of the updated transfer function.

Disclosed is a method for determining a flowed amount of a medium using a first flow measuring transducer according to a first measuring principle and a second flow measuring transducer according to a second measuring principle. The measured values of the first transducer are more reliable in first states of the medium than measured values of the second transducer, and the second measured values are more reliable in second states than the first measured values. A contribution to the flowed amount is ascertained based on the more reliable measured values. The contribution to the flowed amount based on the second measured values is ascertained by means of a transfer function. An updated version of the transfer function is ascertained when the first measured values are more reliable, and the flowed amount earlier ascertained based on the second measured values is corrected as a function of the updated transfer function.

A fluid metering system includes a first and a second fluidic pipe section disposed in parallel between a fluidic pipe inlet and outlet. The first fluidic pipe section includes a first flow control device and a first flow metering device each connected in fluidic series. The second fluidic pipe section includes a second flow metering device connected in fluidic series. The fluidic pipe inlet and the fluidic pipe outlet have the same cross-sectional area and/or flow rate capacity. The first fluidic pipe section has an equal or smaller cross-sectional area and/or flow rate capacity in comparison to the fluidic pipe inlet and outlet. The second fluidic pipe section has a smaller cross-sectional area and/or flow rate capacity in comparison to the cross-sectional area and/or flow rate capacity of the first fluidic pipe section. Alternatively, the second fluidic pipe section may include a second flow control device connected in fluidic series.

The subject matter of this specification can be embodied in, among other things, a fluid flow measurement apparatus includes an inlet configured to flow a dynamic fluid flow, an outlet configured to flow the dynamic fluid flow, a first fluid conduit fluidically connected between the inlet and the outlet, configured with a first predetermined geometry, and configured to flow a first portion of the dynamic fluid flow, a second fluid conduit fluidically connected between the inlet and the outlet, configured with a second predetermined geometry, and configured to flow a second portion of the dynamic fluid flow, and a first flow meter configured to measure the second portion of the dynamic fluid flow.

A measuring system for measuring a mass flow rate, a density, a temperature or a flow velocity. The measuring system includes a main line, a first Coriolis measuring device arranged in the main line, a second Coriolis measuring device arranged in series with the first Coriolis measuring device in the main line, a bypass line which bypasses the second Coriolis measuring device, a first valve arranged in the bypass line, and a computing unit which is connected to the first Coriolis measuring device and to the second Coriolis measuring device. The first valve opens depending on a pressure. The first Coriolis measuring device is designed for a higher maximum flow rate than the second Coriolis measuring device.

A sensor with both Coriolis tube and thermal tube is used to measure the mass flow rate of the fluid using both the Coriolis principle and the thermal method simultaneously. Above certain flow rate, the flow rate is measured by the Coriolis tube and below that flow rate, it is measured by the thermal tube. The Coriolis tube and the thermal tube are arranged parallelly with the common inlet and outlet. Two resistant coils are wound on the thermal tube to do the thermal measurement and a magnetic disk is attached to the Coriolis tube, work together with an excitation coil and two optical sensors to do the Coriolis flow measurement. It takes the advantages of both technologies and create a flow sensor which is super accurate, gas type insensitive, long-term stable and fast responsive without too much pressure drop.

A device for total cross-section measurement of a mass flow rate of gas, liquid and solid in a multiphase flow includes a gamma-ray source, a gamma-ray detector, and a differential pressure type flowmeter. The differential pressure type flowmeter includes a throat section, and the gamma-ray source and the gamma-ray detector are respectively disposed at opposite positions on both sides of the throat section. The gamma-ray detector is an array including a plurality of detection units, and the gamma-ray source is configured to emit gamma rays covering the measurement cross-section of the throat section. The gamma-ray detector is configured to receive the gamma rays passing through the measurement cross-section of the throat section.