托辊附近运动带材稳态构型研究

Steady Configuration of Moving Strip around a Pulley

运动带材在托辊附近的空间分布形态对带材运行安全有着重要影响,针对此,研究了描述带材稳态构型的动边界边值问题,将该问题转化为固定边界边值问题后,采用配置法计算获得带材的稳态构型。给出一组带材构型描述参数,研究了运动带材自身属性及带材工作参数与构型参数的关系。研究表明,带材在带轮附近有隆起趋势,使带材在托辊上的包角减小,对带材的安全运行有不利影响,降低带材的运行速度、减小带材弯曲刚度、增大工作张力、增大托辊直径,有利于缓解此不利影响。带材线密度增大将使隆起高度增加,但隆起段延伸长度将缩短。

To investigate the spatial distribution mode of a moving strip around a pulley and effects of this spatial distribution mode on operation security,a BVP（boundary value problem） with undetermined boundary describing the steady configuration of the moving strip was proposed.After the BVP with undetermined boundary being transformed into a BVP with determined boundary,the steady configuration of the moving strip was solved by using collocation method.Moreover,a set of parameters describing the configuration of moving strip was put forward.Then influencing factors of these parameters were analyzed.The study shows the moving strip will lift up around a pulley.This phenomenon may reduce the wrap angle of the strip on the pulley and it is harmful to the operation security of strip.The influence of this phenomenon can be weakened by reducing moving velocity of the strip and the flexural rigidity of the strip,increasing the tension in strip and the diameter of pulley.Larger linear density makes uplift of the strip higher,but extending length shorter.