The Structure Design And Flow Field Research Of Shipborne Disc Separator

Disc separator is widely used in oil-water separation of ship power system and auxiliary lubricating system because of compact structure and large unit capacity.The separation mechanism of disc separator is elaborated.Drum inner structure is designed based on theoretical formulas and empirical formulas.A two-dimensional geometric model of disc-stack centrifuge for numerical simulation is built and meshed by quadrilateral elements using ICEM CFD software.The numerical simulation is finished in FLUENT software.The result shows that the Oil phase Volume fraction in light outlet comes up to 99.99521%,and the separating effect is pretty good.The influence of different disc angles on separation efficiency is researched:The separation efficiency of 45° model is higher than others,because of the change of flow stress nearby the disc and disc size.The influence of change the disc gap on separation efficiency is researched.The result shows that narrow disc gap has advantages.The prior experimental results verify above-mentioned simulation results.A three-dimensional geometric model of disc-stack centrifuge for numerical simulation is built and meshed by hexahedral elements using ICEM CFD software based on the verified two-dimensional model has been verified,The numerical simulation is finished in FLUENT software.Rationality is affirmed by the results of volume fraction distribution map of oil phase,pressure distribution map and distribution of velocity in the dis gaps.The influence of rotation speed,diameter of water phase and inlet velocity on separation efficiency are researched.The results show that promoting rotation speed could rapidly improve separation efficiency in the condition of constant production capacity.Enlarging the diameter of water phase could improve efficiency within reasonable range.The handling capacity could be improved by promoting inlet velocity,and the efficiency is decreased.Based on the three-dimensional model built above,a three-dimensional numerical simulation in the swing condition is calculated by UDF function in FLUENT software.The swing angle is ±22.5°.The period is 12s,and the swing time of duration is 120s.The results show that the efficiency in the swing condition is lower than efficiency in the steady state condition.A step change exists in every 1/2 period.The rangeability tends to be stable with time lapse.