Patents by Inventor David D. Wickman

David D. Wickman 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: 11125170
    Abstract: An engine/reformer system accepts a first fuel and reforms it into syngas for use as a fuel in an accompanying internal combustion engine. Prior to reforming, the first fuel is pressurized and/or heated to at or near supercritical fluid conditions, such that the resulting syngas leaves the reformer in a supercritical fluid state. Injection of the supercritical syngas into an engine cylinder avoids the autoignition problems that occur when gaseous syngas is used. The first fuel is a fully self-reforming fuel (one that needs no separate water supply for complete conversion to syngas), and can beneficially be a “wet” fuel, such as ethanol containing water, allowing the system to use intermediate products of an ethanol production process (such as hydrous ethanol and stillage wastewater) as fuel, and reducing the overall cost of fuel production and engine operation.
    Type: Grant
    Filed: December 10, 2018
    Date of Patent: September 21, 2021
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Sage L. Kokjohn, David D. Wickman
  • Publication number: 20200182165
    Abstract: An engine/reformer system accepts a first fuel and reforms it into syngas for use as a fuel in an accompanying internal combustion engine. Prior to reforming, the first fuel is pressurized and/or heated to at or near supercritical fluid conditions, such that the resulting syngas leaves the reformer in a supercritical fluid state. Injection of the supercritical syngas into an engine cylinder avoids the autoignition problems that occur when gaseous syngas is used. The first fuel is a fully self-reforming fuel (one that needs no separate water supply for complete conversion to syngas), and can beneficially be a “wet” fuel, such as ethanol containing water, allowing the system to use intermediate products of an ethanol production process (such as hydrous ethanol and stillage wastewater) as fuel, and reducing the overall cost of fuel production and engine operation.
    Type: Application
    Filed: December 10, 2018
    Publication date: June 11, 2020
    Inventors: Sage L. Kokjohn, David D. Wickman
  • Publication number: 20150315957
    Abstract: A compression ignition engine includes a piston having a barrier protruding axially therefrom. The barrier at least partly defines a combustion chamber having a first zone separated from a second zone by the barrier. An initial fuel charge is supplied into the combustion chamber, and a subsequent fuel charge is supplied into the first zone, the subsequent fuel charge having greater reactivity than the initial fuel charge. The fuel charges are compressed to induce ignition and combustion of the fuel charges, such that the subsequent fuel charge burns within the first zone to produce hot gases, and the hot gases flow across the barrier to effect combustion of the initial fuel charge within the second zone.
    Type: Application
    Filed: April 30, 2014
    Publication date: November 5, 2015
    Applicants: Caterpillar Inc., Wisconsin Engine Research Consultants LLC
    Inventors: Michael Joseph Bergin, David D. Wickman, Christopher James Rutland, Rolf Deneys Reitz
  • Patent number: 7389764
    Abstract: A piston for a diesel engine has a crown and a three-dimensional shape defined in an x-y-z coordinate space. The z-axis generally defines a cylinder axis of the piston, and the plane z=0 generally intersects an upper rim of the crown. The piston includes a combustion bowl recessed in the crown. The combustion bowl has a center point on the z-axis and has a two-dimensional partial cross-sectional configuration defined by a peripheral line connecting coordinate points (xi,yi,zi) in the x-y-z coordinate space. The (xi,yi,zi) coordinate points include points from a coordinate set S. The combustion bowl has a three-dimensional axisymmetric configuration defined by rotating the peripheral line 360° about the z-axis.
    Type: Grant
    Filed: January 23, 2007
    Date of Patent: June 24, 2008
    Assignee: GM Global Technology Operations, Inc.
    Inventors: David D. Wickman, Shengming Chang, Ramachandra Diwakar
  • Patent number: 7121254
    Abstract: The present invention is a compression ignition internal combustion engine and method of operation which expands the load limit of quietly operating a premixed charge compression ignition (PCCI) engine by injecting a secondary fuel B, in ratios lean of stoichiometric, either into the intake air stream or directly into the cylinder to form a homogeneous fuel B and air mixture. Near top dead center of the compression stroke, a PCCI-type direct injection of fuel A event is used to initiate combustion of both fuel A and B at the proper time. At low loads the combustion mode is characterized a PCCI-type with high EGR rates. At medium loads the combustion mode is that of homogeneous combustion of fuel B coupled with PCCI combustion of fuel A. At the highest loads the engine will revert to a conventional diesel combustion mode of fuel A to maintain power density.
    Type: Grant
    Filed: February 17, 2005
    Date of Patent: October 17, 2006
    Assignee: General Motors Corporation
    Inventors: David D. Wickman, Carl-Anders Hergart