Numerical experimentation on flow resistance of coal-water slurry in curved pipes

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.