EMISSIONS AND TOTAL ENERGY CONSUMPTION OF A MULTICYLINDER PISTON ENGINE RUNNING ON GASOLINE AND A HYDROGEN-GASOLINE MIXTURE

摘要

An experimental program using a multicylinder reciprocating engine was performed to extend the efficient lean operating range of gasoline by adding hydrogen. Both bottled hydrogen and hydrogen produced by a research methanol steam reformer were used. These results were compared with results for all gasoline. A high-compression-ratio, 7.4-liter (472-in.³ ) dis¬placement production engine was used. Apparent flame speed was used to describe the differ¬ences in emissions and performance. Therefore, engine emissions and performance, including apparent flame speed and energy lost to the cooling system and the exhaust gas, were measured over a range of equivalence ratios for each fuel. The results were used to explain the advan¬tages of adding hydrogen to gasoline as a method of extending the lean operating range. The minimum-energy-consumption equivalence ratio was extended to leaner conditions by adding hydrogen, although the minimum energy consumption did not change. All emission levels de¬creased at the leaner conditions. Also, adding hydrogen significantly increased flame speed over all equivalence ratios. Engine performance and emissions with hydrogen from the methanol reformer were about the same as those with bottled hydrogen.