CAJ | 학술논문

建立了开放性露天堆场周围空气流动的三维数学物理模型，选择应用标准k-ε紊流模型进行了静态流场的数值模拟；分析了典型棱形堆迎风面、平顶面和背风面周围空气的湍流结构和表面受力特性；基于流场数据揭示了防风抑尘网不同孔隙率下空气动力学结构的分布规律.结果显示：物料堆平顶面剪切力随孔隙率增大而增大；料堆迎风面在孔隙率较小时出现局部涡流，表面剪切力方向向下，孔隙率较大时，网后空气垂直方向压差作用显著，表面剪切力方向向上；背风面始终处于回流区，表面剪切力和回流点数随孔隙率大小变化不显著.综合流场结构和受力分布可得最佳孔隙率为0.2~0.4.该研究中对物料堆逐个表面进行空气动力学模拟可以避免由于剪切力方向不同产生矢量抵消而带来的计算失真.
건립료개방성로천퇴장주위공기류동적삼유수학물리모형，선택응용표준k-ε문류모형진행료정태류장적수치모의；분석료전형릉형퇴영풍면、평정면화배풍면주위공기적단류결구화표면수력특성；기우류장수거게시료방풍억진망불동공극솔하공기동역학결구적분포규률.결과현시：물료퇴평정면전절력수공극솔증대이증대；료퇴영풍면재공극솔교소시출현국부와류，표면전절력방향향하，공극솔교대시，망후공기수직방향압차작용현저，표면전절력방향향상；배풍면시종처우회류구，표면전절력화회류점수수공극솔대소변화불현저.종합류장결구화수력분포가득최가공극솔위0.2~0.4.해연구중대물료퇴축개표면진행공기동역학모의가이피면유우전절력방향불동산생시량저소이대래적계산실진.
This paper was conducted to predict the turbulence structure and sheltering effect behind porous fences in open storage piles. The numerical simulation of the three dimensional static flow field was performed applying the standardk-ε turbulence model; the airflow characteristics and the shear stress distribution on the windward side, flat top surface and leeward side of a typical prismatic material stack were analyzed; and the distribution of the aerodynamic structure of each surface of the storage pile was revealed based on the data of flow field for the porous fence with different porosity. Results indicated that the shear force on the flat top surface increased with increasing porosity, exhibited litter change with unfenced conditions. Regarding the windward side of the storage piles, a re-circulating flow in the region between the fence and the pile at low porosities and the shear force acted downward along the windward face, but rather, the shear force acted upward along the windward side at high porosities. Since the leeward side was always in the backflow region, the shear force on the prismatic leeside changed little with increasing porosity. The numerical predictions showed the porous fence with porosity between 0.2and 0.4was found to be the optimum. Through the aerodynamic simulation of each surface of the storage pile, the computation distortion caused by vector offset out of different directions of the shear force can be avoided.