CO2 Cryogenic Liquid Flow Impact on Annular Baffles of Lorry Tanker during Braking

Abstract

The relative motion of cryogenic liquid produces strong impact on tanker structure due to the lorry's acceleration, deceleration, braking and turning. This liquid slashing problem is a dynamic and periodic interaction with fluid structure that reduces movement stability of lorry and its long term service leads baffle and tanker to fatigue fracture. This dynamic and periodic effect leads the baffle and tanker to failure caused by fatigue fracture. So it is of great importance to investigate and minimize the baffle's stress and strain to reduce the fatigue fracture effect. The present work is based on one tanker with effective volume 23.6 m3 for 23630kg CO2 at designed condition of 2.25MPa and -40°C. Two different kinds of typical baffle configuration: annular and chord plate are provided in the same tanker to simulate the liquid flow with time in certain motion mode by CFD. During the early half braking process, the annular baffle distributes fluids into the whole room of the tanker, while the chord plate drives liquid into the lower part of the tanker in the direction of liquid height. The maximum fluid velocity for the annular baffle is 4.70 m/s, less than 4.93 m/s that for chord plate. In this situation, the stress the former suffers is greater than that the latter. Then applied force on the different baffle structures with time is obtained.