Abstract: Cold and hot oils transported alternately in pipelines is a new technology in crude oil transportation, and the appropriate heating scheme to choose is one of the critical technologies. A model, based on the couple of unsteady thermodynamic and hydraulic characteristics to calculate the parameters of batch transportation of cold and hot oils is set up and solved with the finite volume method and the method of thermodynamic characteristic together. The software is developed and verified with the field data gained from one crude oil pipeline in China. Feasibilities of different heating schemes are analyzed by simulating the inlet temperature changing with time. Two different heating-control patterns，heating the low-freezing crude oil entirely or partly, are put forward. Regular variations of minimum heating consumption under two heating-control patterns are studied, and the minimum heating consumption under one heating-control pattern is compared with that under the other. The results show that the minimum consumption of heating oil in the partly heating low-freezing oil is less than that in the entirely heating low-freezing oil.

Key words: cold and hot oils alternation, batch transportation, inlet temperature calculation, heating schemes, heating consumption