密闭式平养鸡舍纵向通风的数值模拟

Numerical simulation of tunnel ventilation system of plane-raising enclosed henhouse

利用计算流体动力学软件Fluent,采用湍流Realizablek-ε模型,对密闭式平养鸡舍矩形进风口风门开启角度、安装高度和进风风速对舍内气流分布的影响进行模拟分析。结果表明:风门开启角度α>0°时,舍内气流分布均匀性较α=0°时有所提高,鸡体水平高度处(距地面0.40 m)的风速随α的增大而增大;在低温季节,为满足鸡体水平高度处风速不大于0.3 m/s(适宜风速)的要求,风门开启角度和最大进风风速的组合可选择为0°、3.0 m/s,15°、1.5 m/s,30°、1.0 m/s和45°、1.0 m/s;进风口距顶棚的距离越小,越易形成贴附射流,而α对贴附射流形成的影响取决于进风口安装高度,因而设计时选择α与进风口安装高度的合适组合,有利于进入舍内的冷空气与舍内热空气的混合。

In this paper,numerical simulation was conducted to analyze the effects of the angel and installation height of the guide plate and air velocity at the inlet on air flow inside the enclosed henhouse. Computational Fluid Dynamics software, Fluent, with turbulent Realizablemode during the calculation was used in this study. The simulation results showed that the uniformity of air distribution inside the henhouse was improved with the guide plate angel a more than 0°. The air velocity at the height of the poultries（0.40 m above the ground）increased with the rise of the guide plate angel. In low temperature seasons,to ensure that the air velocity at the height of poultries will not exceed 0.3 m/s the following combinations of guide plate angles and inlet velocities were recommended ：0° with 3.0 m/s, 15° with 1 .5 m/s, 30° with 1 .0 m/s and 45° with 1 .0 m/s, respectively. The shorter distance between the air inlet and the ceiling will form a wall-jet,which is helpful to mix the incoming colder air with the air inside the henhouse. The influence of a on the uniformity of the air inside the henhouse depends on the air inlet height. The combination of a and the air-inlet height would increase the air mixing inside the henhouse.