SYSTEM APPROACH ACHIEVES CONTROL OF AUTO EMISSIONS

IMPLYING A SIMPLE EXHAUST-GAS-RECIRCULATION SYSTEM, NITROGEN OXIDE EMISSIONS HAVE BEEN REDUCED FROM TWO RESEARCH CARS BY ABOUT 60%. ONE CAR WAS EQUIPPED WITH ENGINE MODIFICATIONS AND THE OTHER CAR WAS EQUIPPED WITH AN EXHAUST MANIFOLD AIR-INJECTION SYSTEM FOR THE REDUCTION OF UNBURNED HYDROCARBONS AND CARBON MONOXIDE EMISSIONS. IN BOTH CASES THE ENGINES WERE MODIFIED TO DIVERT SOME OF THE EXHAUST GASES THAT LEFT THE EXHAUST MANIFOLD AND REINTRODUCED THEM INTO THE INTAKE SYSTEM BETWEEN THE VENTURI AND THE THROTTLE. THE EFFECT WAS TO REDUCE THE HIGH COMBUSTION TEMPERATURES THAT CREATE NITROGEN OXIDES IN THE CYLINDERS. TO CONTROL THE RECYCLE RATE, PLATES WERE INSTALLED WITH SPECIALLY SIZED HOLES THROUGH WHICH THE EXHAUST GASES PASSED. THE SYSTEM RESPONDS TO THE POSITIONS OF A CAR'S THROTTLE. RECIRCULATION OCCURS DURING PARTIALLY-OPEN THROTTLE WHEN THE CAR IS MILDLY ACCELERATING OR CRUISING. DURING WIDE-OPEN OR CLOSED THROTTLE RECIRCULATION IS HARMFUL TO DRIVING TO PERFORMANCE OR UNNECESSARY BECAUSE OF LOWER COMBUSTION TEMPERATURES. ESSO HAS ALSO DEVELOPED AN EXPERIMENTAL SYNCHRO-THERMAL EMISSION CONTROL SYSTEM THAT ACHIEVES AN OVERALL 92% REDUCTION IN UNBURNED HYDROGEN, CARBON MONOXIDE, AND NITROGEN OXIDE EMISSIONS FROM A RESEARCH CAR. THE NEW CONTROL SYSTEM INCLUDES A RICH FUEL-AIR MIXTURE, EXHAUST- MANIFOLD REACTORS, SYNCHRONIZED AIR INJECTIONS INTO THE REACTORS, AND EXHAUST GAS RECIRCULATION. THE SYNCHRO THERMAL SYSTEM IMPLIES A PAIR OF EXHAUST-MANIFOLD REACTORS WHICH MAINTAIN COMBUSTION TEMPERATURES TO BURN MOST OF THE INCREASED HYDROCARBONS IN CARBON MONOXIDE FROM THE CYLINDERS THAT RESULTS FROM THE FUEL INCREASE. THE SYNCHRONIZATION PROMOTES MORE COMPLETE COMBUSTION OF THE UNBURNED HYDROCARBONS IN CARBON MONOXIDE.

• Supplemental Notes:
  • Vol 41, No 6, PP 140, 142, 2 PHOT
• Publication Date: 1970-3-18

Media Info

• Serial:
  • Product Engineering
  • Publisher: McGraw-Hill, Incorporated

Subject/Index Terms

• TRT Terms: Air quality management; Carbon monoxide; Combustion; Emission control systems; Exhaust gases; Hydrocarbons; Nitrogen compounds; Oxides; Temperature
• Old TRIS Terms: Recirculation
• Subject Areas: Highways; Safety and Human Factors; Vehicles and Equipment;

Filing Info

• Accession Number: 00223240
• Record Type: Publication
• Files: TRIS
• Created Date: Aug 3 1970 12:00AM