热油管道停输后初始启动压力波速的计算

热油管道停输后，管内油品降温收缩，管内会产生油蒸气空间，从而使管道再启动时出现启动充装过程。启动压力波速不仅取决于管子的弹性变形和油品的弹性特征，而且与流体的降温幅度和启动流量的大小有关。考虑管子、流体的弹性变形和管内液体的降温收缩，从质量守恒的原则出发，推导了热油管道停输后启动压力波速的计算公式。对长距离热油管道进行的现场试验表明，该公式适用于工程计算。

CALCULATION OF PRESSURE WAVESPE ED OF INITIAL RESTART FOR HOT-OIL PIPELINE

Oil temperature drop and oil contraction can cause gas space growing in oil pipe and line packing during hot oil pipeline shutdown and restarting. The wavespeed of initial restarting pressure depends on not only the elastic deformation of the pipe and oil property, but also the oil contraction and flowrate during restarting. Considering the elastic deformation of the pipe and liquid, and the liquid contraction in the pipe, a formula for calculating the wavespeed of initial restarting pressure is derived according to the principle of mass conservation. Finally, the calculating results are verified by test data in trunk line. The test results show that the formula is favourable for engineering.