SBIR Phase II: Development of an Adaptive Dual-Fuel Injector to Enable

High Efficiency Clean Combustion for SUV and Light Duty Truck Engines

This Small Business Innovation Research (SBIR) Phase II Project will prototype, characterize, and verify performance merits and commercial viability of an Adaptive Dual-Fuel (ADF) Injector. Diesel engines are 30~40% more efficient than port-injection gasoline engines. Gasoline and E85 fuels are among the most widely available fuels, but are mostly used on spark-ignition gasoline engines with much lower thermal efficiency than diesel engines. The key innovation of the ADF injector enables direct-injections of both gasoline/E85 and diesel fuel selectively on-demand from a single injector. The ADF injector can enable simultaneous reduction of NOx and Particulate Matter (PM) emissions and improve engine efficiency through advanced low temperature combustion. The advanced combustion mode enabled by the ADF injector can improve the thermal efficiency of current gasoline/E85 engines by approximately 30~40% by using gasoline and/or E85 fuels in a compression ignition combustion mode. The adaptive dual-fuel injector also provides flexibility for enabling engines to run on either pure diesel, gasoline-diesel, LNG-diesel, or E85-diesel dual fuels. The Phase II work includes prototyping, spray visualization imaging and laser measurements, and single cylinder engine combustion testing to prove commercial viability of the proposed ADF injector.

The broader/commercial impacts of this research are significant potential benefits for energy security and environment protection. The potential customers include engine OEMs and auto makers. This project will significantly benefit US consumers through fuel cost saving, facilitate implementations of new CAFE standards with low cost, and benefit the US economy. The industry-university collaborative engineering research will help graduate students carry out fundamental research while providing deeper understanding of the characteristics of dual fuel injection for practical applications. The dual fuel injector provides new capabilities which can potentially enable transformative combustion methods for ultra-high efficiency clean combustion.


SBIR Phase I: Developing an Adaptive Compact Fuel Reformer with an Ultra-Fine Homogenous Atomizer

This Small Business Innovation Research (SBIR) Phase I Project investigates the merits and feasibility of an Adaptive Compact Fuel Reformer (ACFR) using an Ultra-Fine Homogeneous Atomizer based on an autothermal process. The key innovation of the adaptive compact fuel reformer is an ultra-fine atomizer, which has an innovative micro-circular orifice coupling ultra-thin layer of fuel spray, steam and air flow simultaneously. Innovative design was conducted to develop a unique ultra-fine atomizer along with an effective swirl adapter to enable homogenous mixture formation within the reformer. State of the art laser diagnostics instruments were used to characterize spray distributions and mixture formation of the ultra-fine atomizer. KIVA simulations were conducted to identify the merits of syngas enhanced combustion. Preliminary metal engine testing was also carried out. The results have shown that: (i) The ultra-fine homogenous atomizer (UFHA) provide more uniform spray distribution which is favorable for mixture formation for fuel reformer to reduce wall wetting, thus to reduce potential coking. (ii)Port supplied syngas charge, when combined with advanced in-cylinder direct fuel injection strategies, significantly reduces diesel engine emissions, especially reduce PM and NOx formation, while maintaining and at some cases improving fuel economy by over 10%. The Phase I results provide adequate merits to support further prototyping and engine combustion testing in phase II.

The broader/commercial impacts of this research are significant potential benefits for energy security and environment protection. The potential customers include engine OEMs and auto makers. This research also contributes to fundamental understandings of syngas/hydrogen enhanced high efficiency clean low temperature combustion in general. The industry-university collaborated engineering research helps graduate students conduct fundamental research while providing deeper understanding on diesel fuel reforming for commercial applications.

Recent Publications

  1. Roberts, J., Kokjohn, S., Hou, D., and Huang, Y., "Performance of Gasoline Compression Ignition (GCI) with On-Demand Reactivity Enhancement over Simulated Drive Cycles," SAE Technical Paper 2018-01-0255, 2018.
  2. Kavuri, C.N., Klos, D., Kokjohn S.L., and Hou, D., “Blending the Benefits of Reactivity Controlled Compression Ignition (RCCI) and Gasoline Compression Ignition (GCI) Combustion using an Adaptive Fuel Injection System,” International Journal of Engine Research, 2015. doi: 10.1177/1468087415615255.
  3. Nithyanandan, K., Hou, D., Major, G., and Lee, C., "Spray Visualization and Characterization of a Dual-Fuel Injector using Diesel and Gasoline," SAE Int. J. Fuels Lubr. 7(1):144-158, 2014.
  4. Nithyanandan, K., Huo, M., Lee, C., and Hou, D., "Spray Visualization and Characterization of a Micro-Variable Circular-Orifice (MVCO) Injector Coupled with a Swirl Adapter for Diesel Reformer Applications," SAE Technical Paper 2013-01-1588, 2013.
  6. Hou, D., “A FUEL INJECTOR FOR ON-DEMAND MULTI-FUEL INJECTION,” PCT/US2019/25262, October 1, 2020.
  7. Hou, D., China Patent No. ZL 2005 10200039.9, January 15, 2005.
  8. Hou, D., “A Fuel Injector for Multi-Fuel Injection with Pressure Intensification and a Variable Orifice,” PCT/US2012/068584, December 7, 2012.
  9. Hou, D., “Methods for Low Temperature Combustion and Engines Using the Same,” PCT/US2012/048728, July 27, 2012.
  10. Hou, D., Huang, Y., Huo, M., Cheng, W. et al., "Spray and Atomization Characterization of a Micro-Variable Circular-Orifice (MVCO) Fuel Injector," SAE Technical Paper 2011-01-0679, 2011, doi:10.4271/2011-01-0679.
  11.  Hou, D., Zhang, H., Kalish, Y., Lee, C. et al., "Adaptive PCCI Combustion Using Micro-Variable Circular-Orifice (MVCO) Fuel Injector – Key  EnablingTechnologies for High Efficiency Clean Diesel Engines," SAE Technical Paper 2009-01-1528, 2009, doi:10.4271/2009-01-1528.
  12.  Hou, D., “A Fuel Injector Capable of Dual Fuel Injection,” PCT/US2011/056002, Oct 12, 2011
  13.  Hou, D., “Mixed-Mode Combustion Methods Enabled by Fuel Reformers and Engine Using the Same,“ PCT/US2012/037674, May 12, 2012.
  14.  Hou, D., ”Enabling High Efficiency Clean Combustion with Micro-Variable Circular-Orifice (MVCO) Fuel Injector and Adaptive PCCI,”
  15.  DOE 14th DEERConference, Detroit, MI, August 4~7, 2008.
  16.  Jia, M., Hou, D., Li, J., Xie, M. et al., "A Micro-Variable Circular Orifice Fuel Injector for HCCI Conventional Engine Combustion - Part I Numerical Simulation of  Cavitation," SAE Technical Paper 2007-01-0249, 2007,doi:10.4271/2007-01-0249.
  17.  Hou, D., et al., “A Micro-Variable Circular Orifice (MVCO) Fuel Injector for Zoned Low Temperature Combustion,” 
  18.  DOE 2006 DEER Conference, Detroit, MI, August 20-24, 2006.
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