摘要
本文提出了一种两次求解质量守恒方程、速度与压力协调的求解不可压缩流体流动与传热问题的算法。它采用与SIMPLER求解压力相似的方式,将不含亚松弛因子的离散动量方程转化为假拟速度与压力差的函数,代入到离散质量守恒方程中得到压力方程,以解决压力没有控制方程的问题。通过两次计算假拟速度和求解质量守恒方程,获得同时满足质量守恒与动量守恒的速度和压力,克服了以往的SIMPLE类算法中每一迭代步中速度和压力均不满足动量方程的缺点。有限几个算例表明,新算法的速度松弛因子对收敛速度的影响远小于SIMPLER算法,在松弛因子接近于1时,收敛速度略低于SIMPLER算法,但松弛因子低于0.8时,收敛时间与迭代次数则远小于SIMPLER,算法。
A consistent algorithm that mass conservation equationis required to be solved twice,velocity and pressure can be obtained consistently for solving the problem of incompressible fluid flow and heat transfer is proposed in this paper.Similar to the SIMPLER method for solving pressure,in the consistent algorithm,the discrete momentum equation without underrelaxation factor is cast to the function of pseudovelocity and pressure difference,then an equation regarding pressure can be obtained by substituting the function into the discrete mass conservation equation,thus,the problem that pressure has no control equation was solved.Using the consistent algorithm,the velocity and pressure that simultaneously satisfy mass conservation and momentum conservation can be obtained by calculating the pseudo and solving the mass conservation equation twice,therefore,the disadvantage of classical method that neither velocity nor pressure satisfy momentum conservation at each time step is avoided.Three examples were used to examine the performance of the consistent algorithm,the results show that the effect of velocity relaxation factor on the convergence speed of the new algorithm is much less than that of SIMPLER algorithm,the convergence speed of the new algorithm is slightly slower than that of SIMPLER algorithm when the velocity relaxation is close to 1,but the convergence time and iterations is far less than that of SIMPLER algorithm when the relaxation factor is less than 0.8.
出处
《工程热物理学报》
EI
CAS
CSCD
北大核心
2016年第6期1281-1289,共9页
Journal of Engineering Thermophysics
基金
国家自然科学基金项目(No.51276199)
国家科技重大专项(No.2011ZX05017-004-HZ01)
