James W. Heffel

NOx emission and performance data for a hydrogen fueled internal combustion engine at 1500 rpm using exhaust gas recirculation

Abstract This paper describes six experiments conducted on a 2-liter, 4-cylinder Ford ZETEC internal combustion engine developed to operate on hydrogen fuel. The experiments were conducted to ascertain the effect exhaust gas recirculation (EGR) and a standard 3-way catalytic converter had on NOx emissions and engine performance. All the experiments were conducted at a constant engine speed of 1500 rpm and each experiment used a different fuel flow rate, ranging from 0.78 to 1.63 kg / h . These fuel flow rates correspond to a fuel equivalence ratio, Φ, ranging from 0.35 to 1.02 when the engine is operated without using EGR (i.e. using excess air for dilution). The experiments initially started with the engine operating using excess air. As the experiments proceed, the excess air was replaced with exhaust gas until the engine was operating at a stoichiometric air/fuel ratio. The results of these experiments demonstrated that using EGR is an effective means to lowering NOx emissions to less than 1 ppm while also increasing engine output torque.

NOx emission reduction in a hydrogen fueled internal combustion engine at 3000 rpm using exhaust gas recirculation

Abstract This paper describes five experiments conducted on a 2-l, 4-cylinder Ford ZETEC internal combustion engine (ICE) developed to operate on hydrogen fuel. The experiments were conducted to ascertain the effect exhaust gas recirculation (EGR) and a standard 3-way catalytic converter had on NOx emissions and engine performance. All the experiments were conducted at a constant engine speed of 3000 rpm and each experiment used a different fuel flow rate, ranging from 1.63 to 2.72 kg/h . These fuel flow rates correspond to a fuel equivalence ratio, Φ, ranging from 0.35 to 0.75 when the engine is operated without using EGR (i.e. using excess air for dilution). The experiments initially started with the engine operating using excess air. As the experiments proceed, the excess air was replaced with exhaust gas until the engine was operating at a stoichiometric air/fuel ratio. The results of these experiments demonstrated that using EGR is an effective means to lowering NOx emissions to less than 1 ppm while also increasing engine output torque.

Durability implications of neat hydrogen under sonic flow conditions on pulse-width modulated injectors

Abstract This paper describes the durability implications of neat hydrogen on electronically operated pulse-width modulated fuel injectors. Four injector types were evaluated, some of which were modified through the employment of solid lubricant coatings and surface treatments—creating a total of eight candidate H2 injector variants. For each injector variant, test stand durability data was recorded until failure or the accumulation of more than 800 h ( 64 million injector cycles, or ∼45 k vehicle miles) of operation on neat hydrogen. The injector durability experiments were conducted employing pulse widths and frequencies representative of engine operation at moderate speed, high speed, and maximum speed conditions. The results from these experiments ranged from failure in h to several injector variants successfully completing more than 800 h of testing.