Apparatus and method for measuring velocity and composition of material in and adjacent to a borehole
AssigneeWollin Ventures, Inc.
InventorErnest WOLLIN
Life of this patent
Estimating the term…
Abstract
This disclosure provides systems, methods, and apparatus for measuring flow in and around a borehole of an earth formation. A flow measurement device can include a magnet configured to generate a static solenoidal magnetic field with a field intensity that decreases in strength peripherally from the magnet, an electromagnet disposed around the magnet and configured to generate a time varying solenoidal magnetic field, and a radio frequency (RF) coil disposed around the magnet and configured to generate an RF magnetic field transverse to the static solenoidal magnetic field. The flow measurement device can calculate a flow velocity in and around the flow measurement device based upon a signal received by the RF coil.
Claims20
A flow measurement device for measuring flow in or around a borehole of an earth formation, comprising:
- a magnet configured to generate a static solenoidal magnetic field with a field intensity that decreases in strength peripherally from the magnet;
- an electromagnet disposed around the magnet and configured to generate a time varying solenoidal magnetic field;
- and
- a radio frequency (RF) coil disposed around the magnet and configured to:
- generate an RF magnetic field transverse to the static solenoidal magnetic field and rotating at the Larmor radio frequency corresponding to the field intensity in a region of interest around the flow measurement device;
- and
- output a received signal, the received signal induced by a magnetic field around the RF coil.
A method of measuring flow in or around a borehole in an earth formation, comprising:
- inserting a flow measurement device into the borehole in the earth formation, the flow measurement device comprising a magnet, an electromagnet disposed around the magnet, and a radio frequency (RF) coil disposed around the magnet;
- generating, using the magnet, a static solenoidal magnetic field, wherein the static solenoidal magnetic field has a field intensity that decreases in strength peripherally from the magnet;
- generating, using the electromagnet, a time varying solenoidal magnetic field;
- generating, using the RF coil, an RF magnetic field transverse to the static solenoidal magnetic field and rotating at a Larmor radio frequency corresponding to the field intensity in a region of interest around the flow measurement device;
- and
- receiving a received signal induced in the RF coil by a magnetic field around the RF coil.
Dependencies are inferred from the claim text.