Patents by Inventor Stefan Simescu

Stefan Simescu 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).

  • Diesel engine operation for fast transient response and low emissions
    Patent number: 9062577
    Abstract: A method for controlling emissions in the exhaust gas of a diesel engine, the engine having an exhaust gas recirculation (EGR) system. The engine's exhaust aftertreatment system need have only an oxidation catalyst and a particulate filter (with no NOx reduction or adsorption device). In “normal” engine conditions, the engine is operated with a lean air-fuel ratio, with “normal” engine conditions being engine conditions other than transient load increase engine conditions. Also, during normal engine conditions, the EGR system is used to reduce engine-out NOx. During transient load increase engine conditions, the engine is operated stoichiometrically or near stoichiometrically and the use of EGR is interrupted.
    Type: Grant
    Filed: May 14, 2012
    Date of Patent: June 23, 2015
    Assignee: SOUTHWEST RESEARCH INSTITUTE
    Inventors: Chad P. Koci, Vlad L. C. Ulmet, Stefan Simescu, Magdi K. Khair, Gary D. Neely
  • Diesel Engine With In-Cylinder Soot and NOx Control Using Water or Aqueous Injection
    Publication number: 20140366507
    Abstract: A method of controlling emissions in the exhaust gas of a diesel engine, the engine having one or more combustion cylinders that each generates a combustion jet having a soot region. A water injector is operable to inject a spray of water or aqueous solution into the combustion jet, specifically toward the area of highest soot concentration. This water injection is timed to occur at or immediately before the combustion phase in which the soot reaches its greatest concentration. The size and shape of the spray are such that the majority of the spray reaches the area of greatest soot concentration.
    Type: Application
    Filed: June 17, 2013
    Publication date: December 18, 2014
    Inventors: Stefan Simescu, Vlad L. C. Ulmet
  • Diesel Engine Operation for Fast Transient Response and Low Emissions
    Publication number: 20130304357
    Abstract: A method for controlling emissions in the exhaust gas of a diesel engine, the engine having an exhaust gas recirculation (EGR) system. The engine's exhaust aftertreatment system need have only an oxidation catalyst and a particulate filter (with no NOx reduction or adsorption device). In “normal” engine conditions, the engine is operated with a lean air-fuel ratio, with “normal” engine conditions being engine conditions other than transient load increase engine conditions. Also, during normal engine conditions, the EGR system is used to reduce engine-out NOx. During transient load increase engine conditions, the engine is operated stoichiometrically or near stoichiometrically and the use of EGR is interrupted.
    Type: Application
    Filed: May 14, 2012
    Publication date: November 14, 2013
    Applicant: SOUTHWEST RESEARCH INSTITUTE
    Inventors: Chad P. Koci, Vlad L.C. Ulmet, Stefan Simescu, Magdi K. Khair, Gary D. Neely
  • Passive NOx and PM aftertreatment for diesel engine
    Patent number: 8316633
    Abstract: A method of reducing emissions by operating a diesel engine in a stoichiometric air-fuel ratio mode. To achieve an optimal stoichiometric mode, intake throttling, boost air intake control, fuel injection adjustments, and exhaust gas recirculation (EGR) are used. This mode of operation permits an aftertreatment system that has only an oxidation catalyst and a particulate filter.
    Type: Grant
    Filed: May 29, 2009
    Date of Patent: November 27, 2012
    Assignee: Southwest Research Institute
    Inventors: Magdi K. Khair, Stefan Simescu, Gary D. Neely, Vlad L. C. Ulmet
  • PASSIVE NOx AND PM AFTERTREATMENT FOR DIESEL ENGINE
    Publication number: 20100300073
    Abstract: A method of reducing emissions by operating a diesel engine in a stoichiometric air-fuel ratio mode. To achieve an optimal stoichiometric mode, intake throttling, boost air intake control, fuel injection adjustments, and exhaust gas recirculation (EGR) are used. This mode of operation permits an aftertreatment system that has only an oxidation catalyst and a particulate filter.
    Type: Application
    Filed: May 29, 2009
    Publication date: December 2, 2010
    Applicant: Southwest Research Institute
    Inventors: Magdi K. Khair, Stefan Simescu, Gary D. Neely, Vlad L. C. Ulmet
  • Engine and method for controlling homogenous charge compression ignition combustion in a diesel engine
    Patent number: 6443104
    Abstract: An operating characteristic representative of a first stage reaction in HCCI combustion is sensed and used as a control event for injecting water into the combustion chamber to delay the start of combustion of the primary HCCI reaction.
    Type: Grant
    Filed: December 15, 2000
    Date of Patent: September 3, 2002
    Assignee: Southwest Research Institute
    Inventors: Stefan Simescu, Thomas W. Ryan, III, Daniel W. Dickey
  • Engine and method for controlling homogenous charge compression ignition combustion in a diesel engine
    Publication number: 20020073940
    Abstract: An operating characteristic representative of a first stage reaction in HCCI combustion is sensed and used as a control event for injecting water into the combustion chamber to delay the start of combustion of the primary HCCI reaction.
    Type: Application
    Filed: December 15, 2000
    Publication date: June 20, 2002
    Applicant: SOUTHWEST RESEARCH INSTITUTE
    Inventors: Stefan Simescu, Thomas W. Ryan, Daniel W. Dickey