【摘要】 为了使汽轮机更安全运行,在除湿级的静叶内弧中部开设宽度和喷射角度不同的缝隙除湿结构.对流体区域进行定常三维雷诺平均N-S方程的两相数值模拟,分析热蒸汽喷射对流场的影响.引入火用参数的方法进行能量转化过程的经济性评估.结果表明:同一喷射流量下,顺主流喷射且缝隙宽度越大,喷入热蒸汽的火用值越小且与主流的掺混强度越弱,其火用有效效率越高,即流动损失越小.在喷射流量比小于6%时,各方案的火用有效效率均比无热蒸汽喷射的原型要高.更多还原

【Abstract】 In order to enhance the safe operation of a steam turbine,moisture removal slot configurations with different opening widths and injection angles were in turn set at the central part of a stator inner-arc for the special dehumidifier stage.The flow field was analyzed comparatively by two-phase flow numerical simulation of solving the steady three-dimensional Reynolds averaged Navier-Stokes equations on the basis of real water vapor thermo-physical properties,and the effect of hot steam injection on the flow field was comparatively analyzed.Exergy parameter was introduced as a measure to evaluate the economic cost of energy conversion process.It is indicated that the bigger slot along the mainstream direction requires the lower exergy of hot steam and has the less mixing intensity in the case of the equivalent injected quantity,while it has higher effective exergy efficiency,i.e.the relatively lower flow loss.Moreover,exergy effective efficiency with the mass flow ratio less than 6% is higher than that of the original one without hot steam injection.更多还原