Hydrogen Combustion

The significant and steadily increasing consumption of non-renewable energy driven by daily human activities has contributed to the fossil fuel crisis observed in recent decades. Growing concerns regarding emissions from internal combustion engines are also motivating the search for alternative energy sources to either replace or reduce reliance on conventional nonrenewable fossil fuels. In this context, hydrogen emerges as a promising solution for internal combustion engines to tackle these challenges. Albeit not thoroughly, this review paper aims to address hydrogen combustion as a fuel for gas turbines and internal combustion engines, focusing more on both spark ignition and compression ignition engines, for electricity and heat generation, along with other applications. Use of hydrogen, ammonia and methane as fuel blends in such engines has also been discussed. Most studies reviewed indicate that hydrogenenriched fuels significantly enhance engine performance, particularly in terms of thermal efficiency, fuel consumption and energy utilization. Furthermore, proper operating conditions can lead to substantial reductions in exhaust emissions either carbon or NOx emissions. Notably, the application of hydrogen fuel has resulted in remarkable combustion characteristics in both types of engines. This can be primarily attributed to unique combustion properties of hydrogen, which boasts a higher energy content, higher heating value, rapid flame speed and superior octane rating compared to gasoline, as discussed in this paper. In brief, the use of hydrogen- enriched as a fuel in internal combustion engines has led to enhancements in engine performance, reduced exhaust emissions and improved combustion behavior, achievable under suitable operating conditions and with minor modifications to the engine. Another primary benefit of hydrogen combustion is that it primarily produces water vapor as a byproduct, which greatly reduces greenhouse gas emissions and air pollution in comparison to fossil fuels.