Analysis of Restart Characteristics of Hot Oil Pipeline and Temperature down the Pipeline

Restart process of hot oil pipeline is an unsteady property-variable coupling flow. A mathematical model is established and simulation calculation is conducted with developed computation software aiming at studying pipeline characteristics during restart and the intrinsic law of temperature along pipeline changed with time and flowrate. It is pointed out that pressure drop of pipeline is directly proportional to startup flowrate at different time sequences, but the time to achieve to a steady state flow is shorter instead.