Using ANSYS-CFX, a general purpose fluid dynamics program, the vortex-induced vibration(VIV) of a variable cross-section cylinder is simulated under uniform current with high Reynolds numbers. Large eddy simulation(LE...Using ANSYS-CFX, a general purpose fluid dynamics program, the vortex-induced vibration(VIV) of a variable cross-section cylinder is simulated under uniform current with high Reynolds numbers. Large eddy simulation(LES) is conducted for studying the fluid-structure interaction. The vortex shedding in the wake, the motion trajectories of a cylinder, the variation of drag and lift forces on the cylinder are analyzed. The results show that the vortices of variable cross-section cylinder are chaotic and are varying along the cylinder. In places where cross-sections are changing significantly, the vortices are more irregular. The motion trail of the cylinder is almost the same but irregular. The drag and lift coefficients of the cylinder are varying with the changes of diameters.展开更多
针对一种新型可变气门相异升程汽油机,分析其工作原理,采用Workbench软件的流体分析模块CFX建立仿真分析模型。以相异角、进气门座直径、进气终点压力和进气终点温度为主要参数,通过正交试验设计和仿真分析计算,得到了这些参数对缸内气...针对一种新型可变气门相异升程汽油机,分析其工作原理,采用Workbench软件的流体分析模块CFX建立仿真分析模型。以相异角、进气门座直径、进气终点压力和进气终点温度为主要参数,通过正交试验设计和仿真分析计算,得到了这些参数对缸内气体稳态流动特性的影响。为获得更好的稳态流动特性,利用综合分析法得到主要参数的最佳配置组合为:相异角为8°,进气门座直径为30 mm,进气终点压力为150.0 k Pa,进气终点温度为40℃,仿真分析结果表明,在最佳配置组合条件下缸内气体具有较好的稳态流动特性。展开更多
基金supported by the National Natural Science Foundation of China (Nos. 51179179 and 51079136)
文摘Using ANSYS-CFX, a general purpose fluid dynamics program, the vortex-induced vibration(VIV) of a variable cross-section cylinder is simulated under uniform current with high Reynolds numbers. Large eddy simulation(LES) is conducted for studying the fluid-structure interaction. The vortex shedding in the wake, the motion trajectories of a cylinder, the variation of drag and lift forces on the cylinder are analyzed. The results show that the vortices of variable cross-section cylinder are chaotic and are varying along the cylinder. In places where cross-sections are changing significantly, the vortices are more irregular. The motion trail of the cylinder is almost the same but irregular. The drag and lift coefficients of the cylinder are varying with the changes of diameters.
文摘针对一种新型可变气门相异升程汽油机,分析其工作原理,采用Workbench软件的流体分析模块CFX建立仿真分析模型。以相异角、进气门座直径、进气终点压力和进气终点温度为主要参数,通过正交试验设计和仿真分析计算,得到了这些参数对缸内气体稳态流动特性的影响。为获得更好的稳态流动特性,利用综合分析法得到主要参数的最佳配置组合为:相异角为8°,进气门座直径为30 mm,进气终点压力为150.0 k Pa,进气终点温度为40℃,仿真分析结果表明,在最佳配置组合条件下缸内气体具有较好的稳态流动特性。
