水气二相流与诸多领域的实际工程问题密切相关.对二相流运动进行高精度的数值模拟是计算流体力学研究的难点和热点.针对开敞水域的自由表面流运动问题,将水和空气均视为不可压缩流体,采用五阶加权基本无震荡(weighted essentially non-o...水气二相流与诸多领域的实际工程问题密切相关.对二相流运动进行高精度的数值模拟是计算流体力学研究的难点和热点.针对开敞水域的自由表面流运动问题,将水和空气均视为不可压缩流体,采用五阶加权基本无震荡(weighted essentially non-oscillatory,WENO)格式求解描述流体运动的纳维斯托克斯(Navier–Stokes,NS)方程,利用以加权线性界面算法改进的多维双曲正切函数界面捕捉法(tangent of hyperbola for interface capturing with weighed line interface calculation,THINC/WLIC)追踪水气界面,建立WENO–THINC/WLIC水气二相流运动数值模型.模型采用分步计算法离散求解控制方程,通过压力投影法求解压强场,并利用三阶总变差递减(total variation diminishing,TVD)龙格库塔(Runge–Kutta,RK)法对时间项进行离散求解.通过对环境速度场下Zalesak’s disk和shearing vortex界面运动问题,线性液舱晃荡问题以及溃坝问题的模拟结果与理论分析或试验结果的比较,对所建立的水气二相流数值模型的适用性及模拟精度进行了验证.结果表明,本模型的模拟结果与物理模型或理论分析结果吻合良好,能较为准确地再现不可压缩水气二相流运动现象.鉴于WENO格式和THINC法本身在算法及应用等方面仍在不断改进,本研究提出的WENO–THINC耦合模型为后续更高精度的二相流计算模型开发提供了一种研究思路.展开更多
The application and fundamental study on turbulent premixed combustion of hydrogen enriched natural gas is reviewed in this paper.Discussions include the combustion characteristics of direct injection engine fueled wi...The application and fundamental study on turbulent premixed combustion of hydrogen enriched natural gas is reviewed in this paper.Discussions include the combustion characteristics of direct injection engine fueled with hydrogen enriched natural gas,visualization study of direct injection combustion of hydrogen enriched natural gas using a constant volume vessel,and the fundamental study of turbulent premixed combustion of hydrogen enriched natural gas.The effect of additional hydrogen on the combustion process of natural gas engine is investigated from the fundamental view of the interaction between combustion reaction and turbulent flow.展开更多
文摘水气二相流与诸多领域的实际工程问题密切相关.对二相流运动进行高精度的数值模拟是计算流体力学研究的难点和热点.针对开敞水域的自由表面流运动问题,将水和空气均视为不可压缩流体,采用五阶加权基本无震荡(weighted essentially non-oscillatory,WENO)格式求解描述流体运动的纳维斯托克斯(Navier–Stokes,NS)方程,利用以加权线性界面算法改进的多维双曲正切函数界面捕捉法(tangent of hyperbola for interface capturing with weighed line interface calculation,THINC/WLIC)追踪水气界面,建立WENO–THINC/WLIC水气二相流运动数值模型.模型采用分步计算法离散求解控制方程,通过压力投影法求解压强场,并利用三阶总变差递减(total variation diminishing,TVD)龙格库塔(Runge–Kutta,RK)法对时间项进行离散求解.通过对环境速度场下Zalesak’s disk和shearing vortex界面运动问题,线性液舱晃荡问题以及溃坝问题的模拟结果与理论分析或试验结果的比较,对所建立的水气二相流数值模型的适用性及模拟精度进行了验证.结果表明,本模型的模拟结果与物理模型或理论分析结果吻合良好,能较为准确地再现不可压缩水气二相流运动现象.鉴于WENO格式和THINC法本身在算法及应用等方面仍在不断改进,本研究提出的WENO–THINC耦合模型为后续更高精度的二相流计算模型开发提供了一种研究思路.
基金supported by the National Natural Science Foundation of China(Grant Nos.51376004 and 51006080)the National Basic Research Program of China("973"Program)(Grant No.2013CB228406)
文摘The application and fundamental study on turbulent premixed combustion of hydrogen enriched natural gas is reviewed in this paper.Discussions include the combustion characteristics of direct injection engine fueled with hydrogen enriched natural gas,visualization study of direct injection combustion of hydrogen enriched natural gas using a constant volume vessel,and the fundamental study of turbulent premixed combustion of hydrogen enriched natural gas.The effect of additional hydrogen on the combustion process of natural gas engine is investigated from the fundamental view of the interaction between combustion reaction and turbulent flow.
