为揭示薄壁锥套在运行过程中产生损伤的运行力学机理,提高其运行可靠性,提出一种用于解决具有宏微观跨尺度问题和大规模非线性接触问题的流固耦合方法。通过对薄壁锥套和轧辊所形成的固体域进行三维静电多极离散,采用改进后的Krylov子空间广义极小残值法(GMRES(m))对其进行优化迭代。其中,弹性摩擦接触域进行点面接触非线性数学规划,耦合界面处采用非匹配网格数,并对微米级油膜进行弹性润滑解析和无厚度处理,同时引入Lagrange族内插函数,建立薄壁锥套在宏微观跨尺度下的运行力学模型。通过薄壁锥套运行力学机理试验,验证计算方法在揭示薄壁锥套运行力学行为的正确性。结果表明,薄壁锥套在运行过程中的油膜力场和接触应力场呈三维动态非均匀分布,在复杂交变力场作用下,位于薄壁锥套两端密封槽处的应力奇异性是造成其发生粘结、断裂等破坏的力学原因。在设计阶段必须考虑轧制工况状态,通过设计合适的过盈量和锥套厚度来减小疲劳损伤,提高可靠性。
In order to reveal the operating mechanism of thin-walled cone sleeve damage caused in the running process,and improve the reliability of its operation, a new fluid-solid coupling method is proposed for solving the problem of macro-micro cross-scale problems and large scale nonlinear contact problems. The solid domain formed by sleeve and roll is discretized by three-dimensional electrostatic multipole method and the improved generalized minimal residual method(GMRES(m)) based on Krylov subspace methods is used to optimize and iterate the dense non-symmetric linear equations. Among them, the nonlinear mathematical programming based on point-surface model is used in the elastic friction contact domain, and non-matching grid number is used in the coupling interface. The micron grade oil film is analyzed by elastic lubrication methods and is treated as no thickness. Then Lagrange interpolation function is introduced, and the operating mechanical model of sleeve is established on macro-micro cross-scale. The correctness of this method is verified by the test of the operating mechanics mechanism of the thin-walled cone sleeve. The results show for sleeve in the process of the operation, the distribution of oil film force field and contact stress field are three-dimensional dynamic and non-uniform. And in complex alternating stress field, the high stress singularity of seal groove located at both ends of the sleeve is the mechanics cause of bond, fracture, etc. In the design stage, the rolling condition should be considered, and the fatigue damage can be reduced by the design of the appropriate amount of interference and the thickness of the sleeve.