Patents by Inventor Sage L. Kokjohn

Sage L. Kokjohn 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
  • Patent number: 9376955
    Abstract: A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter.
    Type: Grant
    Filed: June 24, 2015
    Date of Patent: June 28, 2016
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Rolf Deneys Reitz, Reed M. Hanson, Derek A. Splitter, Sage L. Kokjohn
  • Publication number: 20150292391
    Abstract: A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter.
    Type: Application
    Filed: June 24, 2015
    Publication date: October 15, 2015
    Inventors: Rolf Deneys Reitz, Reed M. Hanson, Derek A. Splitter, Sage L. Kokjohn
  • Patent number: 9080501
    Abstract: A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter.
    Type: Grant
    Filed: December 17, 2013
    Date of Patent: July 14, 2015
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Rolf Deneys Reitz, Reed M. Hanson, Derek A. Splitter, Sage L. Kokjohn
  • Patent number: 9057321
    Abstract: A first fuel charge having low reactivity (low cetane number) is injected into a rotary engine, such as a Wankel engine, sufficiently early during the intake stroke that a subsequent higher-reactivity injected fuel charge forms one or more stratified high-reactivity regions within the engine chamber. Compression ignition then begins at the high-reactivity regions and propagates to the lower-reactivity regions. Appropriate choice of the timings, quantities, and other parameters of the injections can allow control of the timing and rate of combustion, such that work output can be maximized, unburned fuel can be minimized, and chamber temperature can be controlled to reduce heat losses and NOx emissions. As a result, rotary engine efficiency can be enhanced while emissions are reduced. Since the invention can be implemented in a lightweight and compact rotary engine, it is well suited for use in hybrid and compact vehicles.
    Type: Grant
    Filed: January 24, 2012
    Date of Patent: June 16, 2015
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Rolf Deneys Reitz, Sage L. Kokjohn
  • Patent number: 8851045
    Abstract: A compression ignition (diesel) engine uses two or more fuel charges during a combustion cycle, with the fuel charges having two or more reactivities (e.g., different cetane numbers), in order to control the timing and duration of combustion. By appropriately choosing the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot). At low load and no load (idling) conditions, the aforementioned results are attained by restricting airflow to the combustion chamber during the intake stroke (as by throttling the incoming air at or prior to the combustion chamber's intake port) so that the cylinder air pressure is below ambient pressure at the start of the compression stroke.
    Type: Grant
    Filed: March 31, 2011
    Date of Patent: October 7, 2014
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Rolf Deneys Reitz, Reed M. Hanson, Derek A. Splitter, Sage L. Kokjohn
  • Publication number: 20140102406
    Abstract: A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter.
    Type: Application
    Filed: December 17, 2013
    Publication date: April 17, 2014
    Applicant: Wisconsin Alumni Research Foundation
    Inventors: Rolf Deneys Reitz, Reed M. Hanson, Derek A. Splitter, Sage L. Kokjohn
  • Patent number: 8616177
    Abstract: A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter.
    Type: Grant
    Filed: February 11, 2010
    Date of Patent: December 31, 2013
    Assignee: Wisconsin Alumni Research Foundation
    Inventors: Rolf Deneys Reitz, Reed M. Hanson, Derek A. Splitter, Sage L. Kokjohn
  • Publication number: 20130186366
    Abstract: A first fuel charge having low reactivity (low cetane number) is injected into a rotary engine, e.g., a Wankel engine, sufficiently early during the intake stroke that a subsequent higher-reactivity injected fuel charge forms one or more stratified high-reactivity regions within the engine chamber. Compression ignition then begins at the high-reactivity regions and propagates to the lower-reactivity regions. Appropriate choice of the timings, quantities, and other parameters of the injections can allow control of the timing and rate of combustion, such that work output can be maximized, unburned fuel can be minimized, and chamber temperature can be controlled to reduce heat losses and NOx emissions. As a result, rotary engine efficiency can be enhanced while emissions are reduced. Since the invention can be implemented in a lightweight and compact rotary engine, it is well suited for use in hybrid and compact vehicles.
    Type: Application
    Filed: January 24, 2012
    Publication date: July 25, 2013
    Inventors: Rolf Deneys Reitz, Sage L. Kokjohn
  • Publication number: 20120247421
    Abstract: A compression ignition (diesel) engine uses two or more fuel charges during a combustion cycle, with the fuel charges having two or more reactivities (e.g., different cetane numbers), in order to control the timing and duration of combustion. By appropriately choosing the reactivities of the charges, their relative amounts, and their timing, combustion can be tailored to achieve optimal power output (and thus fuel efficiency), at controlled temperatures (and thus controlled NOx), and with controlled equivalence ratios (and thus controlled soot). At low load and no load (idling) conditions, the aforementioned results are attained by restricting airflow to the combustion chamber during the intake stroke (as by throttling the incoming air at or prior to the combustion chamber's intake port) so that the cylinder air pressure is below ambient pressure at the start of the compression stroke.
    Type: Application
    Filed: March 31, 2011
    Publication date: October 4, 2012
    Inventors: Rolf Deneys Reitz, Reed M. Hanson, Derek A. Splitter, Sage L. Kokjohn
  • Publication number: 20110192367
    Abstract: A compression ignition engine uses two or more fuel charges having two or more reactivities to control the timing and duration of combustion. In a preferred implementation, a lower-reactivity fuel charge is injected or otherwise introduced into the combustion chamber, preferably sufficiently early that it becomes at least substantially homogeneously dispersed within the chamber before a subsequent injection is made. One or more subsequent injections of higher-reactivity fuel charges are then made, and these preferably distribute the higher-reactivity matter within the lower-reactivity chamber space such that combustion begins in the higher-reactivity regions, and with the lower-reactivity regions following thereafter.
    Type: Application
    Filed: February 11, 2010
    Publication date: August 11, 2011
    Inventors: Rolf Deneys Reitz, Reed M. Hanson, Derek A. Splitter, Sage L. Kokjohn