JOURNAL OF NANJING FORESTRY UNIVERSITY ›› 2016, Vol. 59 ›› Issue (06): 141-147.doi: 10.3969/j.issn.1000-2006.2016.06.022

Previous Articles     Next Articles

Optimizing pulp distributing structure of orifice plate for uniform fiber flow in tapered dstributor

YANG Shuai, LIU Yu, HE Jing, ZHANG Hui*   

  1. Jiangsu Key Lab of Pulp and Paper Science and Technology, Jiangsu Co-Innovation Center for Efficient Processing and Utilization of Forest Resources, Nanjing Forestry University, Nanjing 210037, China
  • Online:2016-12-18 Published:2016-12-18

Abstract: The tapered distributor with orifice plate is widely used in high speed paper machines. In order to make uniform and efficient fiber flow from the distributor into the head box, the vortex near the entrance of the orifice must be eliminated or reduced. The local flow field model of the tapered distributor was firstly drawn with UG software. The grid division was then established with computational fluid dynamics(CFD)method, and the flow field was subsequently simulated with the FLUENT software. Flow characteristics of the tapered distributor with a pedestal shape hole and a straight shape hole were obtained and compared with respect to the distribution contours of the pressure, turbulent kinetic energy, and velocity magnitude in the orifice model. The simulation results showed that, under the experimental condition of 3 m/s pulp flow velocity in distributor, 14 mm diameter of entrance hole and 40 mm diameter of pitch of holes, the vorticity of the flow decreased significantly and slurry flow efficiency increased relatively for the tapered distributor with a pedestal shape hole and round chamfering at the entrance. As the chamfering radius increased, the flow quality improved accordingly. For the multi-hole plate, when the chamfering radius increased up to 1.5 mm, the flow interference between the adjacent holes was the smallest and the most uniform pulp flow distribution was obtained. The pulp fluid condition was the best in this case and the flow efficiency increased by 125.78% compared with that of the straight hole structure. The simulation results of the flow field distribution contour can provide a numerical basis for the improvement of the performance of the tapered distributor with the orifice plate.

CLC Number: