For helical pipe, the secondary flow appears as a loop flow for annular and circular cross section, and a saddle flow for elliptical cross section. 对于螺旋管,圆截面和环形截面上二次流表现为环流,椭圆截面上表现为鞍流。
Analysis of crack near hot reheat pipe saddle and the countermeasures 再热热段管座附近裂纹的原因分析及对策