Patents by Inventor Ravinath Kausik Kadayam Viswanathan

Ravinath Kausik Kadayam Viswanathan has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Publication number: 20210073631
    Abstract: Methods and systems for determining epistemic and aleatoric uncertainties using a dual neural network architecture are described.
    Type: Application
    Filed: September 8, 2020
    Publication date: March 11, 2021
    Inventors: Ravinath Kausik Kadayam Viswanathan, Lalitha Venkataramanan, Augustin Prado
  • Publication number: 20210041414
    Abstract: Nuclear magnetic resonance (NMR) relaxation and/or diffusion measurements are used to deduce fluid compositional information such as a chain-length distribution, which may then be used to predict the true boiling points (TBP) of a sample of a complex hydrocarbon fluid mixture, such as a crude oil. The NMR measurements may be considered a fast and portable proxy measurement in estimating fluid TBP distributions in lieu of distillation methods, or the simulated distillation by gas chromatography.
    Type: Application
    Filed: March 5, 2019
    Publication date: February 11, 2021
    Inventors: Yiqiao TANG, Yi-Qiao SONG, Sharath Chandra MAHAVADI, Ravinath Kausik KADAYAM VISWANATHAN, Shawn David TAYLOR, Gary POTTEN
  • Patent number: 10890685
    Abstract: Nuclear magnetic resonance (NMR) methods and apparatus are provided for investigating a sample utilizing NMR pulse sequences. In various embodiments, the NMR pulse sequences have a solid state portion and a line-narrowing portion. In other embodiments, the NMR pulse sequences have a first line-narrowing portion and a second line-narrowing portion where the sequences of the different portions are different. In yet other embodiments, the NMR pulse sequences have a T1 portion and a line-narrowing portion. Processing of detected signals permits determination of characteristics of the sample including, in some cases, a differentiation of multiple components of the sample.
    Type: Grant
    Filed: August 11, 2017
    Date of Patent: January 12, 2021
    Assignee: Schlumberger Technology Corporation
    Inventors: Ravinath Kausik Kadayam Viswanathan, Yiqiao Song
  • Publication number: 20200408090
    Abstract: Methods and systems are provided that combine NMR and IR spectroscopy measurements on a rock sample to determine data representing at least one property of the rock sample. In one embodiment, cuttings can be split into first and second lots. Results of an NMR measurement performed on the first lot of cuttings without cleaning can be analyzed to determine pore volume of the cuttings. Results of an IR spectroscopy measurement performed on the second lot of cuttings after solvent cleaning can be analyzed to determine matrix density of the cuttings. Porosity can be determined from the pore volume and matrix density of the cuttings. In another embodiment, combined NMR and IR spectroscopy measurements can be performed on an unprepared rock sample (without solvent cleaning) to characterize properties of kerogen in the rock sample and porosity. In another aspect, a method is provided that employs multi-nucleic NMR measurements to determine porosity.
    Type: Application
    Filed: February 11, 2019
    Publication date: December 31, 2020
    Inventors: Ravinath Kausik KADAYAM VISWANATHAN, Shin UTSUZAWA, Kamilla FELLAH, Shawn David TAYLOR, MaryEllen LOAN, Paul Ryan CRADDOCK
  • Publication number: 20200340971
    Abstract: Systems and methods for monitoring a crude oil blending process use nuclear magnetic resonance (NMR) sensors which investigate properties of a plurality of crude oil streams that are mixed together to form a crude oil blend. An NMR sensor is also used to investigate the properties of the crude oil blend. The investigated properties may include viscosity. Resulting determinations may be used to control the input streams so that the output stream meets desired criteria. Additional sensors such as spectroscopy sensors, viscometers, and densitometers may be used in conjunction with the NMR sensors.
    Type: Application
    Filed: December 10, 2018
    Publication date: October 29, 2020
    Inventors: Sharath Chandra Mahavadi, Ravinath Kausik Kadayam Viswanathan, Kamilla Fellah, Simon Ivar Andersen, Yiqiao Tang, Yi-Qiao Song, Shawn David Taylor, Gary Potten
  • Patent number: 10725197
    Abstract: Methods for improved interpretation of NMR data acquired from industrial samples by simultaneously detecting more than one resonant nucleus without removing the sample from the sensitive volume of the NMR magnet or radio frequency probe are disclosed. In other aspects, the present disclosure provides methods for robust imaging/analysis of spatial distribution of different fluids (e.g., 1H, 23Na, 19F) within a core or reservoir rock. NMR data may be interpreted in real-time during dynamic processes to enable rapid screening, e.g. of enhanced oil recovery techniques and products and/or to provide improved interpretation of well-logs. Measurements of resonant nuclei other than 1H may be performed in the laboratory or downhole with a NMR logging tool. In other aspects, the present disclosure describes a novel kernel function to extract values for underlying parameters that define relaxation time behavior of a quadrupolar nucleus.
    Type: Grant
    Filed: September 5, 2017
    Date of Patent: July 28, 2020
    Assignee: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Jonathan Mitchell, Edmund J. Fordham, Lukasz Zielinski, Ravinath Kausik Kadayam Viswanathan
  • Patent number: 10724975
    Abstract: Nuclear magnetic resonance (NMR) methods and apparatus are provided for investigating a sample utilizing NMR pulse sequences having solid state and CPMG pulse sequence portions. Various embodiments of solid state pulse sequences may be utilized including two-dimensional (repetitive) line-narrowing sequences. The hydrogen content of a solid portion of the sample may be determined by using one or more echoes resulting from the solid state sequence portion of the pulse sequence to establish a total organic hydrogen content of the sample, and by using a CPMG echo train to establish a fluid organic hydrogen content, and by subtracting one from the other to obtain the hydrogen content of the sample's solid portion. Additionally, or alternatively, the T2 values obtained from the line-narrowing and CPMG pulse sequences can be compared by plotting to obtain information regarding a characteristic of the sample. The NMR pulse sequence may also include a T1 portion.
    Type: Grant
    Filed: August 11, 2017
    Date of Patent: July 28, 2020
    Assignee: Schlumberger Technology Corporation
    Inventors: Ravinath Kausik Kadayam Viswanathan, Yiqiao Song
  • Patent number: 10705250
    Abstract: A computer-implemented method for reservoir volumetric estimation, a non-transitory computer-readable medium, and a computing system. The method may include running a molecular dynamics simulation of a fluid-rock model of a first reservoir system at a plurality of pressures. The fluid-rock model includes a fluid that is at least partially adsorbed in the first reservoir system at one or more pressures of the plurality of pressures. The method may also include calculating a plurality of isothermal density profiles of the fluid in the first reservoir system, in association with the plurality of pressures using a result of the molecular dynamics simulation. The method may further include determining a first gas accumulation of the fluid in the first reservoir system for the plurality of isothermal density profiles. The first gas accumulation is at least partially a function of a pore surface area of a sample of the first reservoir system.
    Type: Grant
    Filed: July 10, 2014
    Date of Patent: July 7, 2020
    Assignee: Schlumberger Technology Corporation
    Inventors: Mery Diaz Campos, Ravinath Kausik Kadayam Viswanathan
  • Publication number: 20200174153
    Abstract: Downhole properties of a geological formation may be determined using nuclear magnetic resonance (NMR) measurements obtained by a moving tool. To do so, an interpretation of the NMR data obtained by the moving data may take into account a moving model, characterization, or calibration of the downhole NMR tool. Additionally or alternatively, a partial interpretation mask may exclude interpretation of certain areas of data (e.g., T1-T2 data points or diffusion-T2 data points) that are expected to be less likely to describe downhole materials of interest.
    Type: Application
    Filed: May 23, 2018
    Publication date: June 4, 2020
    Inventors: Yi-Qiao Song, Ravinath Kausik Kadayam Viswanathan, Martin Hurlimann, Vivek Anand, Albina Mutina
  • Publication number: 20190383757
    Abstract: Downhole fluid volumes of a geological formation may be estimated using nuclear magnetic resonance (NMR) measurements, even in organic shale reservoirs. Multi-dimensional NMR measurements, such as two-dimensional NMR measurements and/or, in some cases, one or more well-logging measurements relating to total organic carbon may be used to estimate downhole fluid volumes of hydrocarbons such as bitumen, light hydrocarbon, kerogen, and/or water. Having identified the fluid volumes in this manner or any other suitable manner from the NMR measurements, a reservoir producibility index (RPI) may be generated. The downhole fluid volumes and/or the RPI may be output on a well log to enable an operator to make operational and strategic decisions for well production.
    Type: Application
    Filed: August 29, 2019
    Publication date: December 19, 2019
    Inventors: Vivek Anand, Ravinath Kausik Kadayam Viswanathan, Tianmin Jiang, Erik Rylander, Mansoor Ali, Richard E. Lewis
  • Patent number: 10466186
    Abstract: A method for testing an unconventional core sample is provided. The method involves loading the unconventional core sample into a sample holder and introducing fluid into the sample holder at an elevated pressure such that fluid is injected into the internal pore space of the unconventional core sample in order to resaturate the unconventional core sample with the fluid, wherein the fluid is selected from the group including a hydrocarbon fluid and a water-based formation fluid. An apparatus and a system used in combination with the method are also provided.
    Type: Grant
    Filed: January 21, 2015
    Date of Patent: November 5, 2019
    Assignee: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Ravinath Kausik Kadayam Viswanathan, Kamilla Fellah, Erik Rylander, Philip M. Singer, Richard E. Lewis
  • Patent number: 10458894
    Abstract: Methods for analyzing a reservoir in a formation containing hydrocarbon fluid are described. Information characterizing the formation is collected and applied to a formation simulator that is provided with a modified Darcy's law equation that accounts for at least one of gas adsorption/desorption, various modes of diffusive transport, and non-Darcy flow behavior, and the simulator is used to generate indications of the state of the reservoir and/or the state of production of hydrocarbon fluid from the reservoir. The modified Darcy's law equations are particularly useful in analyzing any type of formation containing any type of hydrocarbon fluid including shale formations containing hydrocarbon gases. According to one embodiment, a dual-porosity shape factor useful in a formation simulator is also provided.
    Type: Grant
    Filed: August 12, 2015
    Date of Patent: October 29, 2019
    Assignee: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Wenyue Xu, Mery Diaz Campos, Ravinath Kausik Kadayam Viswanathan
  • Patent number: 10401313
    Abstract: Downhole fluid volumes of a geological formation may be estimated using nuclear magnetic resonance (NMR) measurements, even in organic shale reservoirs. Multi-dimensional NMR measurements, such as two-dimensional NMR measurements and/or, in some cases, one or more well-logging measurements relating to total organic carbon may be used to estimate downhole fluid volumes of hydrocarbons such as bitumen, light hydrocarbon, kerogen, and/or water. Having identified the fluid volumes in this manner or any other suitable manner from the NMR measurements, a reservoir producibility index (RPI) may be generated. The downhole fluid volumes and/or the RPI may be output on a well log to enable an operator to make operational and strategic decisions for well production.
    Type: Grant
    Filed: May 24, 2017
    Date of Patent: September 3, 2019
    Assignee: Schlumberger Technology Corporation
    Inventors: Vivek Anand, Ravinath Kausik Kadayam Viswanathan, Tianmin Jiang, Erik Rylander, Mansoor Ali, Richard E. Lewis
  • Patent number: 10345478
    Abstract: Systems and methods for generating a multi-dimensional distribution function. First data and second data may be received in response to one or more radiofrequency pulses that are transmitted into a subterranean formation. The first data may include Carr-Purcell-Meiboom-Gill data, and the second data may include diffusion editing data with initial echo spacings longer than subsequent echo spacings. The second data may be inverted. A multi-dimensional distribution function may be determined using the inverted second data.
    Type: Grant
    Filed: June 2, 2015
    Date of Patent: July 9, 2019
    Assignee: Schlumberger Technology Corporation
    Inventors: Ravinath Kausik Kadayam Viswanathan, Martin D. Hurlimann, Colm Ryan, Frank P. Shray, Yi-Qiao Song
  • Publication number: 20190049617
    Abstract: Nuclear magnetic resonance (NMR) methods and apparatus are provided for investigating a sample utilizing NMR pulse sequences. In various embodiments, the NMR pulse sequences have a solid state portion and a line-narrowing portion. In other embodiments, the NMR pulse sequences have a first line-narrowing portion and a second line-narrowing portion where the sequences of the different portions are different. In yet other embodiments, the NMR pulse sequences have a T1 portion and a line-narrowing portion. Processing of detected signals permits determination of characteristics of the sample including, in some cases, a differentiation of multiple components of the sample.
    Type: Application
    Filed: August 11, 2017
    Publication date: February 14, 2019
    Inventors: Ravinath Kausik Kadayam Viswanathan, Yiqiao Song
  • Publication number: 20190049397
    Abstract: Nuclear magnetic resonance (NMR) methods and apparatus are provided for investigating a sample utilizing NMR pulse sequences having solid state and CPMG pulse sequence portions. Various embodiments of solid state pulse sequences may be utilized including two-dimensional (repetitive) line-narrowing sequences. The hydrogen content of a solid portion of the sample may be determined by using one or more echoes resulting from the solid state sequence portion of the pulse sequence to establish a total organic hydrogen content of the sample, and by using a CPMG echo train to establish a fluid organic hydrogen content, and by subtracting one from the other to obtain the hydrogen content of the sample's solid portion. Additionally, or alternatively, the T2 values obtained from the line-narrowing and CPMG pulse sequences can be compared by plotting to obtain information regarding a characteristic of the sample. The NMR pulse sequence may also include a T1 portion.
    Type: Application
    Filed: August 11, 2017
    Publication date: February 14, 2019
    Inventors: Ravinath Kausik Kadayam Viswanathan, Yiqiao Song
  • Patent number: 10100636
    Abstract: Levels of kerogen and bitumen are computed in a sample of rock from DRIFTS measurements on the sample. The DRIFTS spectrum of a rock sample is measured, resulting in an estimate of bitumen and kerogen. Bitumen is then washed from the rock and DRIFTS is re-measured, resulting in an estimate of kerogen. Bitumen quantity is calculated by subtracting the washed sampled results from first DRIFTS measurements.
    Type: Grant
    Filed: June 23, 2014
    Date of Patent: October 16, 2018
    Assignee: GEOSERVICES EQUIPEMENTS
    Inventors: Andrew Emil Pomerantz, Robert Leonard Kleinberg, Ravinath Kausik Kadayam Viswanathan, Paul Ryan Craddock
  • Patent number: 10061048
    Abstract: Methods for analyzing a formation samples using nuclear magnetic resonance (NMR) are described herein. One method includes performing an NMR measurement of the formation sample to obtain NMR data. The NMR measurement detects NMR signals with echo times of less than or equal to 100 microseconds. The NMR data is analyzed to determine a measure of organic hydrogen content of the formation sample, such as (i) total organic hydrogen content, (ii) kerogen content, (iii) bitumen content, and/or (iv) oil content.
    Type: Grant
    Filed: July 17, 2014
    Date of Patent: August 28, 2018
    Assignee: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Yi-Qiao Song, Albina Rishatovna Mutina, Ravinath Kausik Kadayam Viswanathan, Martin Hurlimann
  • Publication number: 20180203153
    Abstract: Methods for improved interpretation of NMR data acquired from industrial samples by simultaneously detecting more than one resonant nucleus without removing the sample from the sensitive volume of the NMR magnet or radio frequency probe are disclosed. In other aspects, the present disclosure provides methods for robust imaging/analysis of spatial distribution of different fluids (e.g., 1H, 23Na, 19F) within a core or reservoir rock. NMR data may be interpreted in real-time during dynamic processes to enable rapid screening, e.g. of enhanced oil recovery techniques and products and/or to provide improved interpretation of well-logs. Measurements of resonant nuclei other than 1H may be performed in the laboratory or downhole with a NMR logging tool. In other aspects, the present disclosure describes a novel kernel function to extract values for underlying parameters that define relaxation time behavior of a quadrupolar nucleus.
    Type: Application
    Filed: September 5, 2017
    Publication date: July 19, 2018
    Inventors: Jonathan Mitchell, Edmund J. Fordham, Lukasz Zielinski, Ravinath Kausik Kadayam Viswanathan
  • Patent number: 9880319
    Abstract: Techniques for calculating metrics for reservoir quality based on light oil and total organic carbon in tight oil reservoirs are described. The techniques include calculating quantities of light oil and total organic carbon from logging data and generating therefrom a continuous log for reservoir quality metric. Additionally new reservoir quality indices are presented that more accurately predict reservoir quality in tight oil plays.
    Type: Grant
    Filed: October 2, 2014
    Date of Patent: January 30, 2018
    Assignee: SCHLUMBERGER TECHNOLOGY CORPORATION
    Inventors: Ravinath Kausik Kadayam Viswanathan, Andrew E. Pomerantz, Richard Lewis, Paul Ryan Craddock, Robert L. Kleinberg, Frank P. Shray, Stacy Lynn Reeder Blanco