Powder Technology, Vol.371, 256-266, 2020
Pneumatic vertical transport characteristics of the graphite pebble in a high temperature gas-cooled reactor
A graphite pebble lifting test platform was used to study the aerodynamic characteristics and collision behavior of graphite pebble in the lifting pipe. The impact strength of the pipe wall during pneumatic transport was measured by acceleration sensors and the number of collisions is counted by another visualization experiment. Meanwhile, hydrodynamic theory was combined with a dynamics model of the motion to predict the aerodynamic characteristics and trajectories of the pebble in the lifting pipe. The results show that the aerodynamic force on the graphite pebble increases with increasing inlet velocity and offset. Each graphite pebble in the pipeline follows an upward spiral trajectory due to the aerodynamic forces. The number of graphite pebble impacts decreases with increasing helium pressure due to the shorter residence time, which is in good agreement with experimental results. The present method can provide an efficient method for estimating the impact wear in real HTGR. (C) 2020 Elsevier B.V. All rights reserved.
Keywords:Graphite pebble;Numerical calculation;Dynamic simulation;Collision prediction;High temperature gas-cooled reactor (HTGR)