将两方程k-ωSST湍流模型和Sagaut的混合尺度亚格子模型通过一个混合函数相结合,构造出一种混合大涡/雷诺平均N-S方程模拟方法(hybird large eddy simulation/reynolds-averaged navier-stokes,HybridLES/RANS),采用这种混合模拟方法结...将两方程k-ωSST湍流模型和Sagaut的混合尺度亚格子模型通过一个混合函数相结合,构造出一种混合大涡/雷诺平均N-S方程模拟方法(hybird large eddy simulation/reynolds-averaged navier-stokes,HybridLES/RANS),采用这种混合模拟方法结合5阶WENO格式对Ma=2.8平板湍流边界层进行了数值模拟,并在计算区域上游入口处采用"回收/调节"方法生成湍流脉动边界条件,通过考查RANS区域向LES区域的过渡参数及网格分辨率对这种混合模拟方法进行了评价.计算结果表明:该文采用的混合模拟方法可以捕捉到湍流边界层中的大尺度结构且入口边界层平均参数不会发生漂移,混合函数应当将RANS区域和LES区域的过渡点设置在对数律层和尾迹律层的交界处,而过渡应当迅速以获得正确的雷诺剪切应力分布,在该文采用的模型及数值方法的条件下,流向及展向的网格小至与Escudier混合长相当时,能够获得可以接受的脉动速度的单点-二阶统计值.展开更多
In order to obtain good sintering performance, it is important to understand sintering properties of iron ores. Sintering properties including chemical composition, granulation and high-temperature behaviors of ores f...In order to obtain good sintering performance, it is important to understand sintering properties of iron ores. Sintering properties including chemical composition, granulation and high-temperature behaviors of ores from China, Brazil and Australia. Furthermore, several indices were defined to evaluate sintering properties of iron ores. The results show that： for chemical composition, Brazilian ores present high TFe, low SiOz, and low Alz03 con- tent. For granulation, particle diameter ratio of Brazilian ores are high; particle intermediate fraction of Chinese con- centrates are low; and average particle size and clay type index of Australian ores are high. For high-temperature properties, ores from China, Brazil and Australia present different characteristics. Ores from different origins should be mixed together to obtain good high-temperature properties. According to the analysis of each ore＇s sintering prop- erties, an ore blending scheme （Chinese concentrates 20 ^-1- Brazilian ores 400//oo -k Australian ores 40 ~） was sugges- ted. Moreover, sinter pot test using blending mix was performed, and the results indicated that the ore blending scheme led to good sintering performance and sinter quality.展开更多
文摘将两方程k-ωSST湍流模型和Sagaut的混合尺度亚格子模型通过一个混合函数相结合,构造出一种混合大涡/雷诺平均N-S方程模拟方法(hybird large eddy simulation/reynolds-averaged navier-stokes,HybridLES/RANS),采用这种混合模拟方法结合5阶WENO格式对Ma=2.8平板湍流边界层进行了数值模拟,并在计算区域上游入口处采用"回收/调节"方法生成湍流脉动边界条件,通过考查RANS区域向LES区域的过渡参数及网格分辨率对这种混合模拟方法进行了评价.计算结果表明:该文采用的混合模拟方法可以捕捉到湍流边界层中的大尺度结构且入口边界层平均参数不会发生漂移,混合函数应当将RANS区域和LES区域的过渡点设置在对数律层和尾迹律层的交界处,而过渡应当迅速以获得正确的雷诺剪切应力分布,在该文采用的模型及数值方法的条件下,流向及展向的网格小至与Escudier混合长相当时,能够获得可以接受的脉动速度的单点-二阶统计值.
文摘In order to obtain good sintering performance, it is important to understand sintering properties of iron ores. Sintering properties including chemical composition, granulation and high-temperature behaviors of ores from China, Brazil and Australia. Furthermore, several indices were defined to evaluate sintering properties of iron ores. The results show that： for chemical composition, Brazilian ores present high TFe, low SiOz, and low Alz03 con- tent. For granulation, particle diameter ratio of Brazilian ores are high; particle intermediate fraction of Chinese con- centrates are low; and average particle size and clay type index of Australian ores are high. For high-temperature properties, ores from China, Brazil and Australia present different characteristics. Ores from different origins should be mixed together to obtain good high-temperature properties. According to the analysis of each ore＇s sintering prop- erties, an ore blending scheme （Chinese concentrates 20 ^-1- Brazilian ores 400//oo -k Australian ores 40 ~） was sugges- ted. Moreover, sinter pot test using blending mix was performed, and the results indicated that the ore blending scheme led to good sintering performance and sinter quality.
