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以锅炉省煤器中的流动和换热为应用背景 ,分别采用稳态和非稳态的数学模型对横掠管束的周期性充分发展流动进行了数值模拟 .结果表明 ,在Re大于 15 0到小于 10 0 0的范围内 ,横掠管束的周期性充分发展流动问题是非稳态的 .当采用稳态模型时 ,数值计算结果会随迭代次数的增加而振荡 ,得不到收敛的稳态解 .当采用非稳态模型计算时 ,对节距较小的情况 ,在管的后缘处得到对称的非稳态涡 ;对节距较大的情况 ,在管的后缘处得到周期性脱落的非对称涡 .
Taking the flow and heat transfer in the boiler economizer as the application background, the steady and non-steady mathematical models were respectively used to simulate the periodic fully developed flow of the transversely swept tube bundle.The results show that when Re is greater than 150 to When the steady-state model is used, the numerical results will oscillate with the increase of the number of iterations, and the steady-state solution without convergence can not be obtained When using unsteady model calculations, symmetrical unsteady vortices are obtained at the trailing edge of the pipe for smaller pitches, and periodically at the trailing edge of the pipe for larger pitches Asymmetric vortex.