Emission Control With Lean Operation Using Hydrogen-Supplemented Fuel

Document Number: 740187

Date Published: February 1974

Author(s):
R. F. Stebar - General Motors Corp.
F. B. Parks - General Motors Corp.

Abstract:
Hydrogen-supplemented fuel was investigated as a means of extending lean operating limits of gasoline engines for control of NO\dx. Single-cylinder engine tests with small additions of hydrogen to the fuel resulted in very low NO\dx and CO emissions for hydrogen-isooctane mixtures leaner than 0.55 equivalence ratio. Significant thermal efficiency improvements resulted from the extension beyond isooctane lean limit operation. However, HC emissions increased markedly at these lean conditions.

A passenger car was modified to operate at 0.55-0.65 equivalence ratio with supplemental hydrogen. Vehicle emissions, as established by the 1975 Federal Exhaust Emissions Test, demonstrated the same trends as the single-cylinder engine tests.

The success of the hydrogen-supplemented fuel approach will ultimately hinge on the development of both a means of controlling hydrocarbon emissions and a suitable hydrogen source on board the vehicle. Reported efforts to develop a satisfactory onboard hydrogen generator (gasoline reformer) appear restricted by fuel economy considerations.

File Size: 1705K
Product Status: In Stock

Purchase more technical papers and save! With TechSelect, you decide what SAE Technical Papers you need, when you need them, and how much you want to pay. Learn more >