Performance and emission characteristics of a turbocharged CNG engine fueled by hydrogen-enriched compressed natural gas with high hydrogen ratio

A Review of Hydrogen-Natural Gas Blend Fuels in Internal Combustion Engines

“…Recently, Ma et al (2010) investigated the effect of high hydrogen volumetric content, up to 55%, on the performance of a turbocharged lean burn natural gas engine. The authors found that the addition of hydrogen significantly extends the lean limit, decreases burn duration and yields higher thermal efficiency.…”

“…The effect of hydrogen on the lean limit, here defined as the λ value at which the COV imep attains 10%, is shown in Figure 10 ( Ma et al, 2010), with values of 1.2 for NG, 2.1 for HCNG30 and 2.5 for HCNG55.…”

Hydrogen-Enriched Compressed Natural Gas as a Fuel for Engines

“…Fundamentally, the addition of hydrogen provides a large pool of H and OH radicals whose increase makes the combustion reaction much easier and faster, thus leading to shorter burn duration. Engine performance and emissions at different hydrogen ratios are looked at in more detail in Ma et al (2008h) and Ma et al (2010). …”

Experimental study of the performance and emission characteristics of an adapted commercial four-cylinder spark ignition engine running on hydrogen–methane mixtures

“…The result of these factors is that the power output of a natural gas-fueled engine is typically 10-15% below that of a gasoline engine [4]. Of course, strategies such as direct-injection [5], turbocharching [6] and intercooling can improve the power output although operation under these conditions often leads to increased nitrogen oxides (NO x ) emissions [4]. Exhaust gas recirculation (EGR) is frequently used for reducing NO x emissions from ICEs but in the case of natural gas-fueled engines, the cycle-by-cycle variations of the cylinder peak pressure and the maximum rate of pressure rise increase with the EGR ratio [7].…”

“…The engine, based on the GM 454 one, was adapted for use of gaseous fuels. Ma et al [6,24,32] used an in-line six-cylinder Dongfeng Motor Co. Ltd. engine originally designed for city bus application. The CNG turbocharged SI engine had a displacement volume of 6.2 L and operated with a compression ratio of 10.5:1.…”