Systems and methods for determining water-cut of a fluid mixture

A water-cut sensor system comprising:

• a T-resonator comprising:
• a feed line comprising a conductive material disposed about a first portion of an external surface of a pipe extending in a circumferential direction about the pipe;
• and
• an open shunt stub comprising a conductive material disposed on a second portion of the external surface of the pipe extending in a longitudinal direction along the pipe, the open shunt stub being conductively coupled to the feed line;
• a ground conductor comprising:
• a ground plane comprising a conductive material disposed on a third portion of the external surface of the cylindrical pipe extending in the longitudinal direction along the cylindrical pipe, wherein the third portion of the external surface of the pipe is opposite the second portion of the external surface of the pipe;
• and
• a ground ring comprising a conductive material disposed on a fourth portion of the external surface of the cylindrical pipe extending in a circumferential direction about the pipe, the ground ring being conductively coupled to the ground plane, and the first portion overlapping the fourth portion such that the feed line overlaps the ground ring;
• and
• a separator comprising a dielectric material disposed between the feed line and the portion of the ground ring overlapped by the feed line, the separator being configured to electrically isolate the T-resonator from the ground conductor.

A method for sensing water-cut of a fluid in a cylindrical pipe, the method comprising:

• introducing, to a T-resonator of a water-cut sensor disposed on the cylindrical pipe, source signals of different frequencies, wherein the water-cut sensor comprises:
• the T-resonator comprising:
• a feed line comprising a conductive material disposed about a first portion of an external surface of the pipe extending in a circumferential direction about the pipe;
• and
• an open shunt stub comprising a conductive material disposed on a second portion of the external surface of the pipe extending in a longitudinal direction along the pipe, the open shunt stub being conductively coupled to the feed line;
• a ground conductor comprising:
• a ground plane comprising a conductive material disposed on a third portion of the external surface of the cylindrical pipe extending in the longitudinal direction along the cylindrical pipe, wherein the third portion of the external surface of the pipe is opposite the second portion of the external surface of the pipe;
• and
• a ground ring comprising a conductive material disposed on a fourth portion of the external surface of the cylindrical pipe extending in a circumferential direction about the pipe, the ground ring being conductively coupled to the ground plane, and the first portion overlapping the fourth portion such that the feed line overlaps the ground ring;
• and
• a separator comprising a dielectric material disposed between the feed line and the portion of the ground ring overlapped by the feed line, the separator being configured to electrically isolate the T-resonator from the ground conductor;
• sensing, from the T-resonator of the water-cut sensor, response signals corresponding to the source signals;
• determining a resonance frequency of the water-cut sensor based at least in part on the source signals and the response signals;
• and
• determining a percentage of oil or water in the fluid based at least in part on the resonance frequency of the water-cut sensor.

A method for manufacturing a water-cut sensor, the method comprising:

• disposing a first mask on an external surface of the pipe, the first mask comprising a first opening at a first portion of the external surface of the pipe for forming an open shunt stub of a T-resonator;
• disposing a conductive material into the first opening to form the open shunt stub of the T-resonator on the first portion of the external surface of the pipe;
• disposing a second mask on the external surface of the pipe, the second mask comprising a second opening at a second portion of the external surface of the pipe for forming a ground plane of a ground conductor, the second portion of the external surface being opposite the first portion of the external surface;
• disposing a conductive material into the second opening to form the ground plane of the ground conductor on the second portion of the external surface of the pipe;
• disposing a third mask on an external surface of the pipe, the third mask comprising a third opening at a third portion of the external surface of the pipe for forming a ground ring of the ground conductor, the third portion extending at least from the ground plane about a circumference of the pipe;
• disposing a conductive material into the third opening to form the ground ring of the ground conductor on the third portion of the external surface of the pipe, the ground ring being conductively coupled to the ground plane;
• disposing a dielectric separator on at least a portion of the ground ring to be overlapped by a feed line of the T-resonator;
• disposing a fourth mask on an external surface of the pipe, the fourth mask comprising a fourth opening at an external surface of the dielectric separator for forming the feed line of the T-resonator;
• and
• disposing a conductive material into the fourth opening to form the feed line of the T-resonator on the external surface of the dielectric separator, the feed line being conductively coupled to the open shunt stub.