悬浮式烘箱风嘴结构的优化设计及实验验证

目的 创新设计风嘴泄压孔结构，优化风嘴和基材之间由于气流撞击而形成的涡流，导致基材表面风速温度堆积不均匀的问题。方法 采用Fluent软件，建立单一的风嘴仿真模型，并利用RNG k-ε湍流模型进行数值仿真模拟，分析风嘴有无泄压孔结构对基材干燥特性的影响，并在7种泄压孔设计结构中确定了相对最优方案，通过搭建实验台验证最优风嘴泄压孔结构设计的合理性。结果 实验研究结果表明，通过增设相对最优风嘴泄压孔结构，基材表面涡流产生区域平均风速提高了3.32 m/s，均方差降低了0.86；平均温度提高了24.76K，均方差降低了5.96，表明设计有泄压孔结构的风嘴能明显改善由于涡流堆积造成的风速和温度较低的现象。结论 设计泄压孔结构的风嘴在两狭缝之间区域的风速和温度均有明显提升，涡流区域的压力产生明显下降，改善了风嘴两狭缝之间由漩涡引起的风速、温度较低现象。

Optimized Design and Experimental Verification of Suspended Oven Nozzle Structure

The work aims to innovatively design the structure of the nozzle pressure relief hole to optimize the vortex formed between the nozzle and the substrate due to airflow impingement which leads to the problem of non-uniformity of wind speed and temperature buildup on the surface of the substrate. A single nozzle simulation model was established by Fluent, and numerical simulation was carried out by the turbulence model to analyze the effect of the nozzle with or without pressure relief hole structure on the drying characteristics of the substrate. Meanwhile, the relative optimal scheme was determined among seven designed structures of pressure relief hole, and the reasonableness of the optimal structure design of nozzle pressure relief hole was verified by setting up an experimental bench. The experimental results showed that by adding the relatively optimal nozzle pressure relief hole structure, the average wind speed in the vortex generating area on the surface of the substrate increased by 3.32 m/s, with the mean square deviation decreasing by 0.86, and the average temperature increased by 24.76 K, with the mean square deviation decreasing by 5.96, which indicated that the nozzle with the design of the relief hole structure could significantly improve the phenomena of lower wind speed and temperature due to the buildup of the vortex flow. The nozzle designed with pressure relief hole has a significant increase in wind speed and temperature in the area between the two slits, and the pressure generation in the vortex area decreases significantly, which improves the phenomena of lower wind speed and temperature caused by vortex between the two slits of the nozzle.