The effect of high hydrogen fuel on turbulent combustion in advanced gas turbine combustor with our newly designed arrayed-vanes premixer was studied by large eddy simulation(LES).The dynamic Smagorinsky model is used...The effect of high hydrogen fuel on turbulent combustion in advanced gas turbine combustor with our newly designed arrayed-vanes premixer was studied by large eddy simulation(LES).The dynamic Smagorinsky model is used to calculate the subgrid stress.Finite-rate chemistry is included using a four steps mechanisms.A thickened flame model was used to deal with the reaction rate.The transport and thermal properties are obtained by CHEMKIN packages.The results show that with the increase of hydrogen content,the wake recirculation zone and central toroidal recirculation zone separate.The turbulent fluctuations of H_(2)/air flame first decreases and then increases.For the response of turbulent flame,the results show that the flame brush is narrow and short with the increase of hydrogen content.When the hydrogen content is low,the syngas/air flame can also propagate in the high-speed flow.Therefore,for different flames,the position of outer propagating flame is almost the same.The results also show that the fluctuation of flame intensity increases with the increase of hydrogen content.Although the increase of hydrogen content shortens the chemical reaction time and suppresses the perturbation of turbulent eddies,the cellular instability may further enhance the fluctuation of flame intensity.展开更多
基金supported by the National Natural Science Foundation of China(No.52076007)。
文摘The effect of high hydrogen fuel on turbulent combustion in advanced gas turbine combustor with our newly designed arrayed-vanes premixer was studied by large eddy simulation(LES).The dynamic Smagorinsky model is used to calculate the subgrid stress.Finite-rate chemistry is included using a four steps mechanisms.A thickened flame model was used to deal with the reaction rate.The transport and thermal properties are obtained by CHEMKIN packages.The results show that with the increase of hydrogen content,the wake recirculation zone and central toroidal recirculation zone separate.The turbulent fluctuations of H_(2)/air flame first decreases and then increases.For the response of turbulent flame,the results show that the flame brush is narrow and short with the increase of hydrogen content.When the hydrogen content is low,the syngas/air flame can also propagate in the high-speed flow.Therefore,for different flames,the position of outer propagating flame is almost the same.The results also show that the fluctuation of flame intensity increases with the increase of hydrogen content.Although the increase of hydrogen content shortens the chemical reaction time and suppresses the perturbation of turbulent eddies,the cellular instability may further enhance the fluctuation of flame intensity.
