Patents by Inventor Abdullatif M. Chehab

Abdullatif M. Chehab 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).

  • Patent number: 11536200
    Abstract: A non-contact seal assembly for sealing a gap between relatively rotatable components in a gas turbine engine is presented. The non-contact seal assembly includes a primary seal having a radially movable seal shoe, a mid-plate, an aft secondary seal radially movable along with the seal shoe, a forward secondary seal and a U-shaped seal carrier for holding the components together using pins. The seal shoe includes a plurality of seal shoe segments. The aft secondary seal includes a plurality of aft secondary seal segments. Each aft secondary seal segment is attached to each seal shoe segment. Each aft secondary seal segment includes at least a notch at outer radial side to receive the pin for accommodating radial movement of the seal shoe segment.
    Type: Grant
    Filed: June 5, 2020
    Date of Patent: December 27, 2022
    Assignee: Siemens Energy Global GmbH & Co. KG
    Inventors: Amit K. Paspulati, Abdullatif M. Chehab, Kai Kadau
  • Publication number: 20220268214
    Abstract: A non-contact seal assembly for sealing a gap between relatively rotatable components in a gas turbine engine is presented. The non-contact seal assembly includes a primary seal having a radially movable seal shoe, a mid-plate, an aft secondary seal radially movable along with the seal shoe, a forward secondary seal and a U-shaped seal carrier for holding the components together using pins. The seal shoe includes a plurality of seal shoe segments. The aft secondary seal includes a plurality of aft secondary seal segments. Each aft secondary seal segment is attached to each seal shoe segment. Each aft secondary seal segment includes at least a notch at outer radial side to receive the pin for accommodating radial movement of the seal shoe segment.
    Type: Application
    Filed: June 5, 2020
    Publication date: August 25, 2022
    Inventors: Amit K. Paspulati, Abdullatif M. Chehab, Kai Kadau
  • Patent number: 10519862
    Abstract: A gas turbine engine having a rotor centering cooling system for cooling struts within an exhaust diffuser and turbine case to reduce tip rub during hot restarts is disclosed. In particular, the rotor centering cooling system may be positioned within struts in the exhaust diffuser downstream from a turbine assembly for limiting thermal gradients between top and bottom struts to prevent the exhaust bearing body from becoming off-center during steady state operation as a result of the top struts becoming hotter than the bottom struts. The rotor centering cooling system may reduce the temperature at the exhaust diffuser and turbine case, thereby reducing the thermal gradient between the top and bottom struts and top and bottom of the turbine case. As such, the exhaust bearing body remains centered, thereby preventing a tighter blade tip clearance at the top of the turbine assembly than at the bottom of the assembly.
    Type: Grant
    Filed: June 10, 2014
    Date of Patent: December 31, 2019
    Assignee: Siemens Energy, Inc.
    Inventors: Kok-Mun Tham, Abdullatif M. Chehab, Ross Peterson
  • Publication number: 20180223683
    Abstract: A turbine arrangement including a rotor and a stator surrounding the rotor and comprising guide vane segments, each guide vane segment comprising an airfoil and a radially inner vane platform. A seal arrangement includes a static seal inward from the inner vane platforms and having a radially extending face plate, first and second cylindrical seal walls extending from outer and inner ends of the annular face plate, an annular seal plate extending radially from the second cylindrical seal wall, and an angel wing extending between the first cylindrical seal wall and the annular seal plate to define a first annular cavity and a second annular cavity. Circumferentially spaced cut-outs define passages through the annular seal plate between the first and second annular cavities and are aligned with fasteners that attach the annular face plate to a support ring for supporting the inner vane platform.
    Type: Application
    Filed: July 20, 2015
    Publication date: August 9, 2018
    Inventors: Kok-Mun Tham, Abdullatif M. Chehab, Patrick M. Pilapil, Yan Yin, Christian Xavier Campbell, Vincent Paul Laurello
  • Publication number: 20170138264
    Abstract: A gas turbine engine (10) having a rotor centering cooling system (12) for cooling struts (14) within an exhaust diffuser (16) and turbine case to reduce tip rub during hot restarts is disclosed. In particular, the rotor centering cooling system (12) may be positioned within struts (14) in the exhaust diffuser (16) downstream from a turbine assembly (18) for limiting thermal gradients between top and bottom struts (20) to prevent the exhaust bearing body (24) from becoming off-center during steady state operation as a result of the top struts (20) becoming hotter than the bottom struts. The rotor centering cooling system (12) may reduce the temperature at the exhaust diffuser (16) and turbine case, thereby reducing the thermal gradient between the top and bottom struts (20, 22) and top and bottom (28, 32) of the turbine case.
    Type: Application
    Filed: June 10, 2014
    Publication date: May 18, 2017
    Applicant: Siemens Energy, Inc.
    Inventors: Kok-Mun THAM, Abdullatif M. CHEHAB, Ross PETERSON
  • Patent number: 9091171
    Abstract: A turbine engine including an intermediate space defined between outer and inner portions of the turbine engine. A flow energizer is provided including a flow body located within the intermediate space and including an inlet port, an outlet port and a flow passage extending within the flow body between the inlet and outlet ports. The inlet port receives a flow of a first medium located within the intermediate space and the flow body injects an energizing flow of a second medium to a portion of the first medium within the flow body to create an energized flow of a mixed medium from the outlet portion, the energized flow of mixed medium creates a flow of the first medium adjacent to the flow body within the intermediate space.
    Type: Grant
    Filed: October 30, 2012
    Date of Patent: July 28, 2015
    Assignee: SIEMENS AKTIENGESELLSCHAFT
    Inventors: Jose L. Rodriguez, David A. Little, Jiping Zhang, Abdullatif M. Chehab
  • Patent number: 9068906
    Abstract: Turbine blade tip clearance is measured in a fully assembled turbine casing by mounting a non-contact displacement probe or sensor on a turbine blade that generates data indicative of sensor distance from the turbine casing that circumferentially surrounds the blade. The sensor is mounted on the blade with a sensor fixture, which includes a clamping mechanism and a sensor retention mechanism that retains and calibrates the sensor by selective movement of the sensor relative to the retention mechanism. Variations in sensor distance data are recorded when the turbine is operated in turning gear mode. Blade rotational position data are collected by a rotational position sensor. A data processing system correlates the distance and rotational position data with localized blade tip gap at angular positions about the turbine casing circumference. This method and apparatus facilitate assessment of turbine casing deformation impact on blade tip clearance and rotor/casing alignment.
    Type: Grant
    Filed: October 2, 2013
    Date of Patent: June 30, 2015
    Assignee: Siemens Energy, Inc.
    Inventors: Mahmood K. Silieti, Kevin L. Hines, Abdullatif M. Chehab
  • Patent number: 9062557
    Abstract: A gas turbine having rotor discs (9), a disc cavity (13) and a stator stage (25) extending to the disc cavity (13). Seal housing flanges (43, 44) extend from a seal housing (29) of the stator stage (25). Rotor flanges (41i, 41o) extend from a rotor disk (9-1). An inner rotor flange (41i) and first seal housing flange (43) are inward from a second seal housing flange (44). One rotor flange (41o) is outward from the second seal housing flange (44). The inner rotor flange (41i) and first seal housing flange (43) extend toward one another to limit movement of main gas flow (17). An inlet (47) injects air (50) between the outward rotor flange (41o) and second seal housing flange (44).
    Type: Grant
    Filed: September 7, 2011
    Date of Patent: June 23, 2015
    Assignee: Siemens Aktiengesellschaft
    Inventors: Kok-Mun Tham, Ching-Pang Lee, Abdullatif M. Chehab, Gm Salam Azad, Shantanu P. Mhetras, Manjit Shivanand, Vincent P. Laurello, Christopher Rawlings
  • Patent number: 9003807
    Abstract: The present invention comprises a gas turbine engine and a process for operating a gas turbine engine. A fluid structure receives compressed air from a compressor and extends toward a stationary blade ring in a turbine to discharge the compressed air directly against a surface of the blade ring such that the compressed air impinges on the blade ring surface. The compressed air then passes through at least one opening in the stationary blade ring and into cooling passages of a corresponding row of vanes.
    Type: Grant
    Filed: November 8, 2011
    Date of Patent: April 14, 2015
    Assignee: Siemens Aktiengesellschaft
    Inventors: Abdullatif M. Chehab, David A. Little
  • Publication number: 20150090017
    Abstract: Turbine blade tip clearance is measured in a fully assembled turbine casing by mounting a non-contact displacement probe or sensor on a turbine blade that generates data indicative of sensor distance from the turbine casing that circumferentially surrounds the blade. The sensor is mounted on the blade with a sensor fixture, which includes a clamping mechanism and a sensor retention mechanism that retains and calibrates the sensor by selective movement of the sensor relative to the retention mechanism. Variations in sensor distance data are recorded when the turbine is operated in turning gear mode. Blade rotational position data are collected by a rotational position sensor. A data processing system correlates the distance and rotational position data with localized blade tip gap at angular positions about the turbine casing circumference. This method and apparatus facilitate assessment of turbine casing deformation impact on blade tip clearance and rotor/casing alignment.
    Type: Application
    Filed: October 2, 2013
    Publication date: April 2, 2015
    Inventors: Mahmood K. Silieti, Kevin L. Hines, Abdullatif M. Chehab
  • Publication number: 20140301820
    Abstract: A turbine engine shutdown temperature control system configured to limit thermal gradients from being created within an outer casing surrounding a turbine blade assembly during shutdown of a gas turbine engine is disclosed. By reducing thermal gradients caused by hot air buoyancy within the mid-region cavities in the outer casing, arched and sway-back bending of the outer casing is prevented, thereby reducing the likelihood of blade tip rub, and potential blade damage, during a warm restart of the gas turbine engine. The turbine engine shutdown temperature control system may operate during the shutdown process where the rotor is still powered by combustion gases or during turning gear system operation after shutdown of the gas turbine engine, or both, to allow the outer casing to uniformly, from top to bottom, cool down.
    Type: Application
    Filed: April 3, 2013
    Publication date: October 9, 2014
    Inventors: Uwe Lohse, Evan C. Landrum, Jiping Zhang, Abdullatif M. Chehab
  • Patent number: 8820091
    Abstract: A cooling fluid air injection system for use in a gas turbine engine includes at an external cooling fluid source, at least one rotor cooling pipe, which is used to inject cooling fluid from the source into a rotor chamber, a piping system that provides fluid communication between the source and the rotor cooling pipe(s), a blower system for conveying the cooling fluid through the piping system and the rotor cooling pipe(s) into the rotor chamber, and a valve system. The valve system is closed during full load engine operation to prevent cooling fluid from the source from passing through the piping system, and open during less than full load engine operation to allow cooling fluid from the source to pass through the piping system.
    Type: Grant
    Filed: November 7, 2012
    Date of Patent: September 2, 2014
    Assignee: Siemens Aktiengesellschaft
    Inventors: Kok-Mun Tham, Ching-Pang Lee, Vincent P. Laurello, Abdullatif M. Chehab, David A. Kemp, John A. Fussner, Yan Yin, Bijay K. Sultanian, Weidong Cai
  • Publication number: 20140123657
    Abstract: A cooling fluid air injection system for use in a gas turbine engine includes at an external cooling fluid source, at least one rotor cooling pipe, which is used to inject cooling fluid from the source into a rotor chamber, a piping system that provides fluid communication between the source and the rotor cooling pipe(s), a blower system for conveying the cooling fluid through the piping system and the rotor cooling pipe(s) into the rotor chamber, and a valve system. The valve system is closed during full load engine operation to prevent cooling fluid from the source from passing through the piping system, and open during less than full load engine operation to allow cooling fluid from the source to pass through the piping system.
    Type: Application
    Filed: November 7, 2012
    Publication date: May 8, 2014
    Inventors: Kok-Mun Tham, Ching-Pang Lee, Vincent P. Laurello, Abdullatif M. Chehab, David A. Kemp, John A. Fussner, Yan Yin, Bijay K. Sultanian, Weidong Cai
  • Publication number: 20140119880
    Abstract: A turbine engine including an intermediate space defined between outer and inner portions of the turbine engine. A flow energizer is provided including a flow body located within the intermediate space and including an inlet port, an outlet port and a flow passage extending within the flow body between the inlet and outlet ports. The inlet port receives a flow of a first medium located within the intermediate space and the flow body injects an energizing flow of a second medium to a portion of the first medium within the flow body to create an energized flow of a mixed medium from the outlet portion, the energized flow of mixed medium creates a flow of the first medium adjacent to the flow body within the intermediate space.
    Type: Application
    Filed: October 30, 2012
    Publication date: May 1, 2014
    Inventors: Jose L. Rodriguez, David A. Little, Jiping Zhang, Abdullatif M. Chehab
  • Patent number: 8684669
    Abstract: A measuring assembly for use in a gas turbine engine includes an indicia portion that extends radially inwardly from an inner surface of a ring seal structure to a location radially inwardly from tips of blades mounted on a rotor. The indicia portion of the measuring assembly comprises a section that is abraded by the blades during rotational movement of the rotor to provide a visual indication of a distance between the tips of the blades and the inner surface.
    Type: Grant
    Filed: February 15, 2011
    Date of Patent: April 1, 2014
    Assignee: Siemens Energy, Inc.
    Inventors: Abdullatif M. Chehab, Kevin L. Hines, Barton M. Pepperman, Matthew D. Bogdan
  • Publication number: 20130111919
    Abstract: The present invention comprises a gas turbine engine and a process for operating a gas turbine engine. A fluid structure receives compressed air from a compressor and extends toward a stationary blade ring in a turbine to discharge the compressed air directly against a surface of the blade ring such that the compressed air impinges on the blade ring surface. The compressed air then passes through at least one opening in the stationary blade ring and into cooling passages of a corresponding row of vanes.
    Type: Application
    Filed: November 8, 2011
    Publication date: May 9, 2013
    Inventors: Abdullatif M. Chehab, David A. Little
  • Publication number: 20130058756
    Abstract: A gas turbine having rotor discs (9), a disc cavity (13) and a stator stage (25) extending to the disc cavity (13). Seal housing flanges (43, 44) extend from a seal housing (29) of the stator stage (25). Rotor flanges (41i, 41o) extend from a rotor disk (9-1). An inner rotor flange (41i) and first seal housing flange (43) are inward from a second seal housing flange (44). One rotor flange (41o) is outward from the second seal housing flange (44). The inner rotor flange (41i) and first seal housing flange (43) extend toward one another to limit movement of main gas flow (17). An inlet (47) injects air (50) between the outward rotor flange (41o) and second seal housing flange (44).
    Type: Application
    Filed: September 7, 2011
    Publication date: March 7, 2013
    Inventors: Kok-Mun THAM, Ching-Pang LEE, Abdullatif M. CHEHAB, Gm Salam AZAD, Shantanu P. MHETRAS, Manjit SHIVANAND, Vincent P. LAURELLO, Christopher RAWLINGS
  • Publication number: 20120207586
    Abstract: A measuring assembly for use in a gas turbine engine includes an indicia portion that extends radially inwardly from an inner surface of a ring seal structure to a location radially inwardly from tips of blades mounted on a rotor. The indicia portion of the measuring assembly comprises a section that is abraded by the blades during rotational movement of the rotor to provide a visual indication of a distance between the tips of the blades and the inner surface.
    Type: Application
    Filed: February 15, 2011
    Publication date: August 16, 2012
    Inventors: Abdullatif M. Chehab, Kevin L. Hines, Barton M. Pepperman, Matthew D. Bogdan
  • Publication number: 20120183389
    Abstract: A sealing system for a rotor assembly in a gas turbine engine is disclosed. The sealing system may include a seal formed from a side block and an upper seal that seals a gap between a radially outward extending first rotor supply channel in a rotor assembly terminating at an inlet of an axially extending second rotor supply channel that is in fluid communication with an internal blade cooling system of a turbine blade. The seal may include components that enhance the flow of cooling fluids over conventional configurations. In another embodiment, the sealing system may include an integrated sealing block configured to seal a gap between adjacent turbine blades at an intersection between the first and second rotor supply channels. The integrated sealing block may be formed from a radially inward extending leg and central body.
    Type: Application
    Filed: January 13, 2011
    Publication date: July 19, 2012
    Inventors: Shantanu P. Mhetras, Manjit Shivanand, Abdullatif M. Chehab, Ching-Pang Lee
  • Patent number: 7708518
    Abstract: A system and method for actively managing blade tip clearances in a turbine engine, particularly under steady state operating conditions such as at base load, involves routing a portion of air from a rotor cooling air circuit to a vane carrier or other stationary support structure surrounding the turbine blades. Because the temperature of the air is less than the temperature of the stationary support structure, the stationary support structure will thermally contract when the air is passed in heat exchanging relation therewith. In one embodiment, the air can be passed through one or more passages extending through at least a portion of the stationary support structure. The contraction of the stationary support structure reduces the blade tip clearance because the blades do not contract. Thus, fluid leakage through the clearances is minimized, which in turn can increase engine performance.
    Type: Grant
    Filed: June 23, 2005
    Date of Patent: May 4, 2010
    Assignee: Siemens Energy, Inc.
    Inventor: Abdullatif M. Chehab