多孔射流式通风的流场特性分析

为了分析多孔射流风机作用下风场的流场特性，文中采用CFD方法，对多孔射流式风场模型内部流场进行了数值模拟，对比分析了不同喷嘴数量及排布方式对流场性能的影响，并引入涡动力学理论，分析了流场内涡结构的分布发展规律及其对流体掺混的影响。结果表明：喷嘴的数量及排布方式对流场性能有显著影响，外围喷嘴会对中心喷嘴的流动起到限制作用；流向涡对流体掺混效果的作用比展向涡大，在涡量一定的情况下，流向涡尺度越大、衰减越快，流体间的混合效果越好，流场稳定性越高。流场内速度及涡动力学分布表明，流场稳定性随着喷嘴数量的增加而显著提高，因此在保证经济性的前提下应尽量采用数量多的喷嘴排布方式。

Analysis of Flow Field Characteristics of Multi-nozzle Jet Ventilation

To analyze the flow field characteristics of the wind field under the action of the porous jet fan, the CFD method is used to simulate the internal flow field of the porous jet wind field model, and the effects of the number and arrangement of nozzles on the flow field performance are compared and analyzed. The theory of vortex dynamics is introduced to analyze the distribution and development of vortex structure in the flow field and its influence on fluid mixing effect. The simulation results show that the arrangement of nozzles has a significant impact on the flow field performance, and the peripheral nozzles will restrict the flow of the central nozzle; the streamwise vortex has a greater effect on the fluid mixing effect than the spanwise vortex. In the case of a constant vortex, a larger flow vortex scale and faster attenuation is advantageous to the flow field stability. The velocity and vortex dynamics distribution in the flow field show that the stability of the flow field increases significantly with the increase of the number of nozzles. Therefore, the number of nozzle arrangements should be used as much as possible on the premise of ensuring economy.