菊花热风烘房的流场模拟及结构优化

Flow-field simulation and structural optimization of the chrysanthemum hot air drying room

采用多孔介质模型对结构优化前后菊花热风烘房烘干室的流场进行了数值模拟研究,根据引风罩角度与长度提出了9种优化方案,考察了不同引风罩下烘干室气流组织的分布特性。结果表明:烘干室原始结构在进风口局部区域风速过大,前后、上下空间内风速较小,气流组织分布不均匀。相比原始结构,9种优化方案中,引风罩θ=20°,L=150 mm的烘干室流场的多个截面风速不均匀系数M分别由123.23%,113.10%,76.14%,69.29%,91.93%,113.57%降至93.71%,93.34%,73.62%,61.18%,88.09%,96.17%,综合优化效果最佳。结构优化后的烘干室进风口速度过大区域缩小,气流向四周的扩散性提高,整体空间气流均匀性得到改善。

In this article,the porous-media model is used to numerically study the flow field of the chrysanthemum hot air drying room before and after the structural optimization.A total of 9 optimization schemes are proposed according to the air-guide cover’s angle and length.The distribution characteristics of airflow in the drying room with different air-guide covers are taken into account.The results show that the original structure of the drying room has excessive wind speed in the local area of the air inlet,wind speed in the front-back and upper-lower space is small,and airflow is unevenly distributed.The new structure,compared with its original counterpart,enjoys better effect of optimization on the whole,with the air-guiding coverθ=20°and L=150 mm.The wind-speed deviation coefficient M in multiple sections reduces from 123.23%,113.10%,76.14%,69.29%,91.93%and 113.57%to 93.71%,93.34%,73.62%,61.18%,88.09%and 96.17%respectively.After the structure is optimized,the airinlet area with excessive wind speed shrinks,the diffusivity of airflow increases,and the uniformity of airflow in the space improves.