Abstract: A flow meter obtains the individual flow rates of gas, liquid hydrocarbons, and water in a predominantly gas-containing flowing fluid mixture. The flow meter comprises a water content meter (7) provides a signal representing a measure of the water content of said fluid. It also comprises a double differential pressure generating (3) and measuring (4) structure, denoted a DDP-unit (2), that provides two measurement signals (6A and 6B) representing two independent values of differential pressure (DP) in said fluid (1). In addition to the above, the meter also comprises a signal processing unit (8) having inputs (9A-C) for receiving the measurement signals and the water content signal, and a calculation module (10) which calculates values representing the volumetric flow rates of said gas, liquid hydrocarbons and water in said fluid.

Abstract: Apparatus for measuring the composition and flow rate of a fluid (1) comprising a mixture of e.g. oil and water in a pipe (2), wherein an integrated mechanical structure (3) serves as a microwave resonator sensor for providing permittivity measurements and where the mechanical structure also functions as a differential pressure element for providing flow rate measurements.

Abstract: Apparatus for measuring the composition and flow rate of a fluid (1) comprising a mixture of e.g. oil and water in a pipe (2), wherein an integrated mechanical structure (3) serves as a microwave resonator sensor for providing permittivity measurements and where the mechanical structure also functions as a differential pressure element for providing flow rate measurements.

Abstract: A microwave sensor (3) for measuring the relative proportions of fluids is provided. The sensor (3) includes a tube (4) having a length (9) for accommodating the fluids flowing through said tube. The length (9) of the tube (4) makes up a part of the sensor (3). Also included are probes (6, 7) for transmitting electromagnetic energy into the sensor (3) and receiving electromagnetic energy from the sensor (3). The sensor (3) uses resonance at a resonant frequency (fm) below the cut-off frequency (fm) of the tube (4). The tube (4) includes at least one radially extending, conducting, internal fin (5) extending along the axis (10) of the tube (4). The fin (5) may be of regular or irregular shape and may be fixedly or detachedly arranged, e.g., through a slot (13).