燃氢燃气轮机的变工况特性

Characteristics of Hydrogen Gas Turbine in Off-design State

建立了考虑空气冷却的燃气轮机系统的变工况模型,对掺氮燃烧方式和纯氢燃烧方式下燃气轮机的变工况性能进行了计算和分析.利用Chemkin中基于氢气燃烧机理的燃烧模型,对2种燃烧方式下燃烧室内的燃烧特性进行了计算和分析,比较了燃烧区流体速度、层流火焰速度、点火延迟时间和NOx排放量.结果表明:采用纯氢燃烧方式的燃气轮机在扭矩裕度、喘振裕度和透平出口温度三方面的变工况性能都更优,但燃烧室内面临更高的回火可能性和NOx排放量.

A hydrogen gas turbine model considering cooling air has been set up,with which the gas turbine characteristics in off-design state were studied according to nitrogen-blended and pure-hydrogen two combustion modes.Chemkin combustion models based on hydrogen combustion mechanism were applied to calculate and analyze the characteristics of the combustion in off-design state,comparing the gas velocity in reaction zone,laminar flame speed,auto-ignition delay time, NO_x emission of the two combustion modes.Results show that in terms of system characteristics in off-design state,the gas turbine in pure hydrogen combustion mode has dominant advantages over that in nitrogen-blended mode,such as on the aspect of torque margin,surge margin and outlet temperature,except for its disadvantages of higher flashback possibility and higher NO_x emission.