contrarily, the optimal rotate speed and the optimal operation point of the turbine can be obtained from the mean optimal incident angle. 反之，利用文中给出的平均最佳进气迎角也可确定透平的最佳转速，进而确定最佳工况点。
contrarily, I will write in English first, in doing this, I can practice thinking in English. 相反地，我会先写英文，这样做，我才可以锻炼用英语思考。
