A numerical method based on 3 D turbulence flow was applied to simulate the flow pattern in suction boxes of six different types. In light of the computational results, the basic flow patterns in the boxes were revea...A numerical method based on 3 D turbulence flow was applied to simulate the flow pattern in suction boxes of six different types. In light of the computational results, the basic flow patterns in the boxes were revealed and a theoretical method to optimize hydraulically design of the suction box is developed. The box geometrical parameters, which influence the flow pattern in the box, could be optimized. The optimum criteria for the hydraulic design of the suction boxes of six types established, respectively. Furthermore, a summarization is given here based on the classification of the basic flow patterns in order to systematically understand the hydraulic design of suction boxes.展开更多
针对汽车前防撞梁吸能盒模具设计存在每分钟生产速度(speed per minute,SPM)未能达到SPM40标准的问题,通过多次试模以及结合经验,分析存在不良问题的原因。结合模具结构设计提出相应修改方案,最终通过调试确认在满足制件精度等要求情况...针对汽车前防撞梁吸能盒模具设计存在每分钟生产速度(speed per minute,SPM)未能达到SPM40标准的问题,通过多次试模以及结合经验,分析存在不良问题的原因。结合模具结构设计提出相应修改方案,最终通过调试确认在满足制件精度等要求情况下,模具SPM可达45冲次,提高了生产效率。展开更多
Suction boxes are used in the paper industry to simultaneously drain a pulp suspension and form a fibre mat （or filter cake）. This research addresses the modelling of fibre deposition in the forming unit of an indus...Suction boxes are used in the paper industry to simultaneously drain a pulp suspension and form a fibre mat （or filter cake）. This research addresses the modelling of fibre deposition in the forming unit of an industrial papermachine, assuming a filtration process, and that of the flowing suspension drained through the building fibre mat and the wire on a suction box. From experimental data of the cumulative drained V volume, per unit surface area, for two vacuum pressures △P and 6 dwell times t, an extension of the classical law （t/V） versus V is proposed, validated and applied. This relation enables determining the average specific filtration resistance of the fibre mat over the box and the mass of solids deposited before and over the suction box. The model obtained is as precise as 1% and can be used to limit and reduce the energy consumption of drainage vacuum assisted devices such as suction boxes in the forming unit of industrial papermachines.展开更多
文摘A numerical method based on 3 D turbulence flow was applied to simulate the flow pattern in suction boxes of six different types. In light of the computational results, the basic flow patterns in the boxes were revealed and a theoretical method to optimize hydraulically design of the suction box is developed. The box geometrical parameters, which influence the flow pattern in the box, could be optimized. The optimum criteria for the hydraulic design of the suction boxes of six types established, respectively. Furthermore, a summarization is given here based on the classification of the basic flow patterns in order to systematically understand the hydraulic design of suction boxes.
文摘Suction boxes are used in the paper industry to simultaneously drain a pulp suspension and form a fibre mat （or filter cake）. This research addresses the modelling of fibre deposition in the forming unit of an industrial papermachine, assuming a filtration process, and that of the flowing suspension drained through the building fibre mat and the wire on a suction box. From experimental data of the cumulative drained V volume, per unit surface area, for two vacuum pressures △P and 6 dwell times t, an extension of the classical law （t/V） versus V is proposed, validated and applied. This relation enables determining the average specific filtration resistance of the fibre mat over the box and the mass of solids deposited before and over the suction box. The model obtained is as precise as 1% and can be used to limit and reduce the energy consumption of drainage vacuum assisted devices such as suction boxes in the forming unit of industrial papermachines.
