Patents by Inventor Rahul Mital

Rahul Mital 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: 8479500
    Abstract: An exhaust system for an engine comprises a selective catalytic reduction (“SCR”) device having a NOx reducing selective catalytic reduction composition disposed thereon. A particulate filter is disposed in the rigid shell or canister downstream of the selective catalytic reduction device. An ammonia dosing system comprising a controller in signal communication with NOx sensors located upstream and downstream of the selective catalytic reduction device for injection of ammonia into the exhaust gas upstream of the SCR device based on information collected from the NOx sensors to thereby optimize the reduction of NOx in the exhaust gas. An ammonia-neutral oxidation catalyst compound is disposed on the wall-flow substrate of the particulate filter device and is configured to pass through ammonia constituents of the exhaust gas exiting the selective catalytic reduction device with little or no conversion of the ammonia constituents to N2, N2O and NOx.
    Type: Grant
    Filed: April 8, 2011
    Date of Patent: July 9, 2013
    Assignee: GM Global Technology Operations LLC
    Inventors: Shouxian Ren, Rahul Mital, Jason Daniel Mullins
  • Publication number: 20130091830
    Abstract: An assembly for mixing liquid within a gas flow includes a hollow conduit that is configured for containing a flow of gas and liquid droplets. The assembly also includes multiple spaced blades and an impingement element. Each of the blades is operatively connected to and extends from the impingement element and is connected to an inner wall of the conduit. The impingement element is upstream of the blades in the flow of gas. The impingement element and the blades are configured to create a preferred distribution of the liquid droplets within the gas flow downstream of the blades within the conduit.
    Type: Application
    Filed: October 18, 2011
    Publication date: April 18, 2013
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Jianwen Li, James B. Rodgers, Chijou Wang, Rahul Mital
  • Publication number: 20130025266
    Abstract: An exhaust gas treatment system for an internal combustion engine is provided and includes an exhaust gas conduit, a hydrocarbon supply, a particulate filter (“PF”), at least one sensor, a first temperature sensor, a second temperature sensor, and a control module. The PF is in fluid communication with the exhaust gas conduit and has a filter structure for removal of particulates in the exhaust gas. The filter structure has an innermost region and an outermost region. The PF is selectively regenerated during operation of the internal combustion engine. The PF has a stratified temperature structure that causes the particulates trapped at the innermost region of the PF burn off before the particulates trapped in the outermost region of the PF during regeneration. The control module has a memory with an infinite stage temperature control curve stored thereon.
    Type: Application
    Filed: July 26, 2011
    Publication date: January 31, 2013
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Jianwen LI, Rahul Mital, Michael V. Taylor, Thomas Larose, JR., Thomas J. Sobtzak, Paul Jasinkiewicz, Rebecca J. Darr
  • Publication number: 20120258015
    Abstract: An exhaust system for an engine comprises a selective catalytic reduction (“SCR”) device having a NOx reducing selective catalytic reduction composition disposed thereon. A particulate filter is disposed in the rigid shell or canister downstream of the selective catalytic reduction device. An ammonia dosing system comprising a controller in signal communication with NOx sensors located upstream and downstream of the selective catalytic reduction device for injection of ammonia into the exhaust gas upstream of the SCR device based on information collected from the NOx sensors to thereby optimize the reduction of NOx in the exhaust gas. An ammonia-neutral oxidation catalyst compound is disposed on the wall-flow substrate of the particulate filter device and is configured to pass through ammonia constituents of the exhaust gas exiting the selective catalytic reduction device with little or no conversion of the ammonia constituents to N2, N2O and NOx.
    Type: Application
    Filed: April 8, 2011
    Publication date: October 11, 2012
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Shouxian Ren, Rahul Mital, Jason Daniel Mullins
  • Publication number: 20120204541
    Abstract: According to one aspect of the invention, a mixer element to be placed between an internal combustion engine exhaust manifold and catalytic converter is provided. The mixer element includes a tubular conduit that receives an exhaust gas flow from the internal combustion engine, a first mixer configured to induce a first vortex of the exhaust gas flow in a first rotational direction and an injector disposed in the tubular conduit downstream of the first mixer, the injector being configured to inject a diesel emission fluid flow into the exhaust gas flow. The mixer element also includes a second mixer positioned downstream of the injector and a third mixer positioned downstream of the second mixer, the third mixer being configured to induce a second vortex of the exhaust gas flow and the diesel emission fluid mixture in a second rotational direction, opposite of the first rotational direction.
    Type: Application
    Filed: February 14, 2011
    Publication date: August 16, 2012
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS LLC
    Inventors: Jianwen Li, Rahul Mital, Kimberly O'Kane, Shouxian Ren
  • Patent number: 8146351
    Abstract: An exhaust control system includes a temperature sensor, a temperature estimation module, and an exhaust condition adjustment module. The temperature sensor measures an outlet temperature of an exhaust gas downstream from an emission reduction device. The temperature estimation module estimates a highest temperature of the emission reduction device. The exhaust condition adjustment module controls operation of the exhaust control system based on the highest temperature of the emission reduction device.
    Type: Grant
    Filed: June 5, 2009
    Date of Patent: April 3, 2012
    Inventors: Jianwen Li, Michael Christopher Luckham, Paul Jasinkiewicz, Rebecca J Darr, Rahul Mital
  • Patent number: 8043394
    Abstract: A particulate matter (PM) filter assembly includes a PM filter that filters PM from an exhaust stream and that includes an entry face facing a first direction of flow of the exhaust stream, and a swirl element disposed in the exhaust stream and that includes a blade that directs a portion of the exhaust stream in a second direction of flow that is different than the first direction of flow. The blade directs the portion of the exhaust stream to distribute the exhaust stream over a frontal area of the entry face of the PM filter. A related method of filtering particulate matter from an exhaust stream is also provided.
    Type: Grant
    Filed: October 15, 2008
    Date of Patent: October 25, 2011
    Inventors: Rahul Mital, David B. Brown, Jianwen Li, Michael Christopher Luckham, Kevin B. Fuqua, Kasser A. Jaffri, Linda Garcia
  • Publication number: 20110239624
    Abstract: An exhaust gas treatment system for an internal combustion engine comprises an exhaust gas conduit in fluid communication with the internal combustion engine to conduct the exhaust gas between a plurality of exhaust treatment devices. A hydrocarbon injector in fluid communication with the exhaust gas delivers hydrocarbon thereto. A selective catalyst reduction device is disposed downstream of the hydrocarbon injector and is configured to receive and mix the hydrocarbon and exhaust gas and to reduce components of NOx therein. An oxidation catalyst device is disposed in fluid communication with the exhaust gas conduit downstream of the selective catalyst reduction device and is configured to oxidize exhaust gas and hydrocarbon mixture to raise the temperature of the exhaust gas. A particulate filter assembly is located downstream of the oxidation catalyst device for receipt of the heated exhaust gas, and combustion of carbon and particulates collected in the exhaust gas filter.
    Type: Application
    Filed: April 6, 2010
    Publication date: October 6, 2011
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Jianwen LI, Rahul MITAL
  • Patent number: 7908845
    Abstract: A mixing apparatus mountable within a generally cylindrical passage defined by an exhaust gas conduit of an exhaust gas after-treatment system is provided. The passage includes an outer region and an inner region operable to convey an exhaust stream and a liquid stream, such as a urea stream. The mixing apparatus includes a retainer ring operable to retain the mixing apparatus within the passage. A first plurality of fins extends from the retainer ring and is operable to impart a rotational velocity component in a first direction to the exhaust stream and urea stream in the outer region of the passage. A second plurality of fins extends from the retainer ring and is operable to impart a rotational velocity component in a second direction, opposite the first direction, to the exhaust stream and urea stream in the inner region of the passage.
    Type: Grant
    Filed: April 16, 2007
    Date of Patent: March 22, 2011
    Assignee: GM Global Technology Operations LLC
    Inventors: David B. Brown, Rahul Mital, Kasser A. Jaffri, Kevin B. Fuqua
  • Patent number: 7900441
    Abstract: The invention provides a NOx adsorber aftertreatment system for internal combustion engines which utilizes at least one precat operatively coupled to at least one NOx adsorber to aid in the regeneration of the NOx adsorber. Fuel is injected into a precat located upstream of a NOx absorber producing heat, H2O, and reductants such as CO, HC, and volatile hydrocarbons, which are input into the NOx absorber. The combination of heat, water, and reductants help to efficiently regenerate the NOx Adsorber which in turn releases exhausts products such as CO2 and N2. Regeneration of a NOx adsorber can be performed during periods of reduced exhaust gas flow lowering the fuel penalty associated with NOx adsorber regeneration. The pre-cat, NOx adsorber regenerating aftertreatment system of the present invention may be used with any suitable control system.
    Type: Grant
    Filed: February 12, 2004
    Date of Patent: March 8, 2011
    Assignee: Fleetguard, Inc.
    Inventors: Rahul Mital, Bradlee J. Stroia, Shyancherng C. Huang, Robert C. Yu
  • Publication number: 20100326059
    Abstract: In one exemplary embodiment of the present invention, an exhaust aftertreatment system is disclosed. The system includes an oxidation catalyst (OC) that is configured to receive an exhaust gas flow from an engine. The system also includes an uncoated particulate filter (PF) that is configured to receive the exhaust gas flow from the OC. The system further also includes an exhaust fluid (EF) dosing device configured for dosing of an EF into the exhaust gas flow upstream of the uncoated PF. Still further, the system includes a selective catalyst reduction (SCR) catalyst that is configured to receive the exhaust gas flow from the uncoated PF, wherein the OC, uncoated PF and SCR catalyst comprise an exhaust aftertreatment system. A urea injector may be provided as the EF dosing device and arranged to inject urea, for example, into the exhaust gases upstream of the uncoated PF.
    Type: Application
    Filed: January 11, 2010
    Publication date: December 30, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Rahul Mital, Jianwen Li
  • Publication number: 20100319320
    Abstract: An exhaust gas treatment system for a diesel engine is disclosed. The exhaust gas treatment system includes a lean NOX trap (LNT) in fluid communication with a diesel engine to receive an exhaust gas flow therefrom. The system also includes a two-way catalyst in fluid communication with the LNT to receive the exhaust gas flow therefrom, the two-way catalyst comprising a urea selective catalytic reduction catalyst and a diesel particulate filter (DPF).
    Type: Application
    Filed: June 17, 2009
    Publication date: December 23, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Rahul Mital, David B. Brown, Yongsheng He, Jong H. Lee
  • Publication number: 20100319324
    Abstract: An exhaust gas treatment system for a diesel engine is disclosed. The exhaust gas treatment system includes a hydrocarbon selective catalytic reduction catalyst (HC-SCR) in fluid communication with a diesel engine to receive an exhaust gas flow therefrom. The system also includes a two-way catalyst in fluid communication with the HC-SCR to receive the exhaust gas flow therefrom, the two-way catalyst comprising a urea selective catalytic reduction catalyst and a diesel particulate filter (DPF).
    Type: Application
    Filed: June 17, 2009
    Publication date: December 23, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventor: Rahul Mital
  • Publication number: 20100307139
    Abstract: An exhaust control system includes a temperature sensor, a temperature estimation module, and an exhaust condition adjustment module. The temperature sensor measures an outlet temperature of an exhaust gas downstream from an emission reduction device. The temperature estimation module estimates a highest temperature of the emission reduction device. The exhaust condition adjustment module controls operation of the exhaust control system based on the highest temperature of the emission reduction device.
    Type: Application
    Filed: June 5, 2009
    Publication date: December 9, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Jianwen Li, Michael Christopher Luckham, Paul Jasinkiewicz, Rebecca J Darr, Rahul Mital
  • Patent number: 7814744
    Abstract: An exhaust after-treatment system for an internal combustion engine includes a lean NOx catalyst having an exhaust stream from the internal combustion engine flowing therethrough. A NOx absorber catalyst is downstream of the lean NOx catalyst. The NOx absorber is selectively regenerated to increase a NOx reduction efficiency of the exhaust after-treatment system.
    Type: Grant
    Filed: August 24, 2006
    Date of Patent: October 19, 2010
    Inventor: Rahul Mital
  • Publication number: 20100242438
    Abstract: The present invention is directed towards methods and systems for treatment of exhaust gas from an engine. In one embodiment, an exhaust gas treatment system for a diesel engine is provided. The system includes a urea selective catalytic reduction (U-SCR) catalyst in fluid communication with a diesel engine to receive an exhaust gas flow therefrom. The system also includes a four-way catalyst in fluid communication with the U-SCR catalyst to receive the exhaust gas flow therefrom, the four-way catalyst comprising a lean nitrogen oxide (NOX) trap (LNT) and diesel particulate filter (DPF).
    Type: Application
    Filed: March 26, 2009
    Publication date: September 30, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventor: Rahul Mital
  • Publication number: 20100242448
    Abstract: The present invention is directed towards methods and systems for treatment of exhaust gas from an engine. In one embodiment, an exhaust gas treatment system for a diesel engine includes a four-way catalyst in fluid communication with a diesel engine to receive an exhaust gas flow therefrom, the four-way catalyst comprising a lean nitrogen oxides (NOX) trap and a diesel particulate filter (DPF). The system also includes a urea selective catalytic reduction (U-SCR) catalyst in fluid communication with the four-way catalyst to receive the exhaust gas flow therefrom.
    Type: Application
    Filed: March 26, 2009
    Publication date: September 30, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventor: Rahul Mital
  • Publication number: 20100242461
    Abstract: The present invention provides an exhaust cooler mounted to a tailpipe for receiving exhaust gas. The exhaust cooler includes a jet pump connectable to the tailpipe and a nozzle connectable to the tailpipe. The nozzle defines a nozzle opening between the tailpipe and the jet pump for communicating the exhaust gas from the tailpipe to the jet pump. A first throttle member is included that is moveable between a closed position and an open position, the open position defining a first opening between the tailpipe and the jet pump for communicating the exhaust gas from the tailpipe to the jet pump.
    Type: Application
    Filed: June 7, 2010
    Publication date: September 30, 2010
    Applicant: GM GLOBAL TECHNOLOGY OPERATIONS, INC.
    Inventors: Jianwen Li, Rahul Mital
  • Patent number: 7784275
    Abstract: A diesel engine system having an exhaust system with a catalyst and a diesel particulate filter includes a first module that determines a light-off temperature of the catalyst based on an exhaust flow rate (EFR) through the exhaust system and a second module that selectively generates an enable signal based on the light-off temperature and a catalyst temperature. A DPF regeneration sequence is enabled based on said enable signal.
    Type: Grant
    Filed: September 23, 2005
    Date of Patent: August 31, 2010
    Inventors: Chad E. Marlett, Rahul Mital
  • Patent number: 7757482
    Abstract: The present invention provides an exhaust cooler mounted to a tailpipe for receiving exhaust gas. The exhaust cooler includes a jet pump connectable to the tailpipe and a nozzle connectable to the tailpipe. The nozzle defines a nozzle opening between the tailpipe and the jet pump for communicating the exhaust gas from the tailpipe to the jet pump. A first member is included that is moveable between a closed position and an open position, the open position defining a first opening between the tailpipe and the jet pump for communicating the exhaust gas from the tailpipe to the jet pump.
    Type: Grant
    Filed: February 21, 2007
    Date of Patent: July 20, 2010
    Assignee: GM Global Technology Operations, Inc.
    Inventors: Jianwen Li, Rahul Mital