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在9-22 MPa亚临界压力区,基于Fortran程序针对不同螺纹结构的垂直上升内螺纹管汽水单相和两相流动的摩擦压降特性进行数值对比研究.研究表明:螺纹结构对内螺纹管的流动特性有显著影响;与光管相比,内螺纹管有较大的摩擦系数,摩擦系数随着内螺纹管螺纹当量N的增加而增大;内螺纹管的两相摩擦压降倍率φl02在低干度值时受N值影响较小,压强越大,差距越小;φl02随压力增大而减小,随蒸汽干度χ增加2l0φ先增加,随后增幅减小,在χ>0.9时有下降的趋势.研究结果为动力工程中内螺纹管的优化提供理论依据.
In the 9-22 MPa subcritical pressure region, based on the Fortran program, the frictional pressure drop characteristics of single-phase and two-phase flow of vertically rising female pipe with different thread structures were compared. The results show that: Compared with the light pipe, the internal pipe has a larger coefficient of friction, the friction coefficient increases with the increase of the equivalent N of the female pipe. The frictional pressure drop magnification of the internal pipe is Low dryness value is less affected by the N value, the greater the pressure, the smaller the gap; φl02 decreases with increasing pressure, with the increase of the dryness χ 2l0φ first increase, then the increase decreases, when χ> 0.9 Declining trend.The results provide theoretical basis for the optimization of the female threaded pipe in power engineering.