Patent ID: 11867629
Assignee: SAUDI ARABIAN OIL COMPANY
Field: Measurement (Instruments)
Classification: CPC G  E | IPC E  G

Claim 0:
1. A sensing system for monitoring a composition of a downhole fluid in a well, the sensing system comprising:
at least one light source, having at least one frequency comb generator, that emits a beam;
a first optical switch configured to split the beam into a reference beam and a sensing beam;
a waveguide;
an evanescent field sensing element that is in direct contact with the downhole fluid, wherein
the frequency comb generator is configured to modify the reference beam into a reference comb beam and to modify the sensing beam into a sensing comb beam,
the evanescent field sensing element is configured to provide attenuated internal reflection of the sensing comb beam at an interface between the evanescent field sensing element and the downhole fluid,
the sensing comb beam interacts with the downhole fluid to form at least a portion of an interacted beam;

a second optical switch that combines the sensing comb beam after interacting with the downhole fluid and the reference comb beam to form the interacted beam having an interferogram, wherein
the downhole fluid is arranged between the first optical switch and the second optical switch, and
the sensing comb beam interacts with the downhole fluid at the evanescent field sensing element, and the reference comb beam bypasses the downhole fluid, and

a detector configured to obtain a spectral distribution of at least one of the following: the beam, the sensing comb beam, the reference comb beam, the interacted beam, or a combination thereof.