【摘要】 结合管流法和旋转粘度计法对神华煤水煤浆进行了流变特性测量,得出符合屈服—幂律流体模型的水煤浆流变方程。利用CFD软件平台建立了水煤浆90°弯管的流动模型,通过计算值与实验值的比较,验证了计算模型的正确性。运用正确的计算模型对水煤浆流经弯管的局部阻力系数进行了多变量数值模拟实验,得出了弯管工程设计中最佳弯径比与流速的关系,总结出适合工程应用的水煤浆流经较小弯径比时的局部阻力系数的经验公式。且弯管内最大速度点随弯径比的增大往弯管外侧移动;随弯径比或弯曲角度的增大,弯管内的速度场趋于一致。更多还原

【Abstract】 Based on the pipe flow method and the rotational viscometer method,the rheological behavior of Shenhua coal-water slurry was measured and the rheological equation in conformity with the model of Herschel-Bulkley was gained.The model of coal-water slurry flow in a curved 90o bend was established by using CFD software platform,and the computational model was proved correct through comparison between calculated values and experimental values.With the correct computational model,numerical experiments on local resistance coefficient was conducted,providing the interrelations between the best bend diameter ratio and flow velocity in engineering design as well as the empirical equation of local resistance coefficient for practical engineering.It is also concluded that with increasing of the bend diameter ratio the dot of maximum velocity is near to the wall outside of a pipe bend,and the distribution of the velocity field in the pipe tends to become the same with increasing of the bend diameter ratio or the bend angle.更多还原