Abstract: Based on FLUENT multiphase model(VOF).finite-volume method is used to establish a mathematical model for contamination of batch transportation.Numerical simulation on pipeline transportation process for the cold oil and hot oil via 90 elbow and 10 m's fall in turn is carried out.Taking the Daqing Crude Oil and Russian Crude Oil as an example, influence of different transportation sequence, flow rate and oil temperature on contamination density is analyzed.Results show that increasing transportation rate can reduce the contamination length during cold oil and hot oil batch transportation, and at given flow rate, for the forward Russian Crude Oil with lower density and viscosity, the relatively lower the temperature for the trailing Daqing Crude Oil is.the smaller the mixed volume is; for the trailing Russian Crude Oil with lower density and viscosity, the relatively higher the temperature for the forward Daqing Crude Oil is.the smaller the mixed volume is.which are matched with the actual running pipeline.