【摘要】 有限元计算汽轮机转子热应力时,计算速度和精度受到计算机性能和网格密度的限制。采用合理的隔离体模型对加快计算速度与保证计算精度有重要意义。利用某型1 000MW汽轮机高压转子模型,计算了整体转子模型及不同隔离体模型在机组启动工况下的热应力,探讨了隔离体模型选取的可行性。计算结果表明,合适的隔离体模型完全可以代替整体转子模型进行热应力计算。采用隔离体模型省去对汽轮机各级蒸汽参数的计算,仅需计算隔离体所包含的前几级蒸汽参数,且计算过程中大大简化了边界条件的输入,在保证结果精度的前提下,提高了计算效率。更多还原

【Abstract】 On the process of calculating steam turbine thermal stress by finite element method,proper isolation model takes paramount significance on accuracy and rate of calculation. This paper calculates the start-up thermal stress of a 1000 MW steam turbine HP rotor,using the integral model and different isolation model. Result shows that appropriate isolation model absolutely could be used in thermal stress calculation as a substitute of integral model. This method requires only a few calculation of steam parameters in forward stages,instead of all stages. Besides,it simplifies the input of boundary conditions. As a result,the calculation efficiency is greatly enhanced on the premise of an assurance of calculation accuracy.更多还原