THE IMPORTANCE OF SECONDARY AIR MIXING IN EXHAUST THERMAL REACTOR SYSTEMS

Automotive thermal reactors have obtained high conversion efficiencies on engines with very rich carburetion, but fuel economy and reactor durability have suffered. Improved mixing of exhaust gas and secondary air in the engine exhaust port was examined as a means of improving reactor efficiency at less rich engine air-fuel ratios. Three air-injection systems which span a broad range of mixing capabilities were examined. High-pressure, timed air injection provides the best mixing and the best reactor performance. Sparger (radial discharge) air injection tubes provide fair mixing and better performance than conventional open-ended air injection tubes, which exhibit poor mixing characteristics. Performance with sparger tubes is significantly poorer than with timed injection, but sparger tubes are more practical in terms of cost, complexity, and durability. /GMRL/

• Corporate Authors:

  Society of Automotive Engineers (SAE)

  400 Commonwealth Drive
  Warrendale, PA  United States  15096
• Authors:
  • Herrin, R J
• Publication Date: 1975-2

Media Info

• Pagination: 14 p.

Subject/Index Terms

• TRT Terms: Emission control systems; Engines; Exhaust gases; Fuel air mixtures; Fuel injection; Thermal reactors
• Uncontrolled Terms: Air fuel ratio
• Subject Areas: Highways; Safety and Human Factors; Vehicles and Equipment;

Filing Info

• Accession Number: 00099137
• Record Type: Publication
• Report/Paper Numbers: SAE #750174
• Files: TRIS
• Created Date: Nov 5 1975 12:00AM