Temperature drop calculation in hot waxy crude pipeline during shutdown

Key words:  hot oil pipeline  waxy crude  shutdown  temperature drop  numerical simulation  calculation

Abstract:

The temperature drop in hot oil pipelilne during shutdown was simulated using CFD software of Fluent. The simulation need not follow the moving of solid liquid phase interface during the wax precipitation process and can invert the latent heat to additional heat absorption capacity. The comparison between the experimental and the simulated results shows that the influences of natural convection and the moving of phase interface during the temperature drop process can be displayed, which makes the solving of this kind of problem more easy. Based on this method, the influence of the initial oil temperature and the pipeline diameter on the temperature drop process of the underwater pipeline was studied. The results show that, both increasing the pipe diameter and raising initial oil temperature can prolong shutdown duration. Moreover, increasing the pipe diameter is more effective to prolong shutdown duration while other conditions are the same.