Prediction of bulging by approximation model of contact state between roll and strand - computation of three-dimensional deformation behavior of continuously cast steel strand in multiroll spans II

摘要

In our previous paper, a computational method to analyze three-dimensional deformation behavior of continuously cast steel strands in the steady state in multiroll spans has been proposed, where two approximations for the contact state between the cast strand and the support rolls have been introduced by penalty functions, that is, (a) the strand passes through only the roll gap and (b) the inner product of the strand velocity and the normal vector on the roll surface at the roll gap point is zero. In this paper, the bulging deflections of a slab in a single roll-span and multiroll (4 and 8) spans are considered as computational examples for examining (i) the validity of the proposed approximations and (ii) the influence of the penalty value, K{sub}n, in approximation (b) on the bulging deflections. The comparison of the computed results with the experimental results by Wunnenberg confirms the validity of approximation (a). From the computational results, it is found that the approximation (b) is valid for a short roll span (the length of the roll span, L, is less than 430mm) and K{sub}n>9.8·10{sup}6Nmm{sup}(-1)s.