Investigation of Flow and Combustion Technology Changes in a Device Nozzle for Natural Gas as a Result of Mixing in Hydrogen

Abstract

The efforts of the European Union (2021, EU Regulation on Gas and Hydrogen Networks) have been waiting for a solution to the problem of -even if only partial- independence from natural gas. The article shows the effects on the combustion technical parameters and equipment, if the 100% natural gas plant is replaced with a certain proportion of hydrogen. The article examines how it affects the combustion technical parameters of natural gas user equipment if the gas that feeds them is replaced by hydrogen-natural gas mixtures of different proportions. The results show that with the introduction of hydrogen, the Wobbe number decreases, and with this equipment, hydrogen can be added to the natural gas in an amount of 23 V/V% so that it meets the standards. When examining the flame propagation speed, we conclude that it is expected that the flame will not burn back at this ratio. The work promotes the progress of natural gas-hydrogen co-combustion technologies, as it examines a special part of the combustion equipment, the nozzle, and the flow engineering processes taking place in it. With the help of this model, we successfully investigated the excess air resulting from various natural gas-hydrogen mixtures in the case of a given geometry, but the model, with its mathematical additions, also proves that mixing in hydrogen generally reduces the amount of incoming air.