Development of Next Generation Wiping Air Knifese

下一代擦拭气刀的开发

• 批准号: 433947-2012
• 负责人: Ziada, Samir
• 金额: $ 1.78万
• 依托单位: McMaster University
• 依托单位国家: 加拿大
• 项目类别: Engage Grants Program
• 财政年份: 2012
• 资助国家: 加拿大
• 起止时间: 2012-01-01 至 2013-12-31
• 项目状态: 已结题
• 来源: https://www.nserc-crsng.gc.ca/ase-oro/Details-Detailles_eng.asp?id=510875
• 关键词: Development; Next; Generation; Wiping; Air

In continuous hot dip galvanizing, a high speed planar air jet, known as an "air knife", is used on each side of the sheet steel substrate to control the thickness of the zinc coating. The impingement of these jets on the moving steel sheet, after its immersion in a bath of molten zinc, causes the excess molten zinc to be wiped back into the zinc bath. To date, only single-slot jets are used in galvanizing industry and other thermal processing applications such as glass tempering, heating of complex surfaces, cooling of turbine blades and for the cooling of electronic devices. The objective of the proposed research work is to develop new air knife geometries consisting of multiple slot jets, which can be designed to produce specific and desired combinations of pressure gradient and shear stress distribution on the steel sheet and thereby facilitate superior coating weight control for a wide range of galvanizing process parameters. The use of multiple slot jets, instead of a single jet, is also expected to reduce pressure fluctuations on the steel strip which improves the coating quality and its weight consistency and reduces the noise generated by the air knives. It is further anticipated that use of the multiple jet technology will allow lower coating weights to be produced than is currently possible with the single jet technology, thereby overcoming this limitation of the current single jet technology. This Engage proposal deals with the first phase of this project and the requested funding will be used to establish a multiple-slot jet facility and measurement techniques. A versatile test facility consisting of a multiple-slot jet impinging on a plate will be designed, manufactured and commissioned. This initial phase will also include intensive use of Laser Doppler Velocimetry and Particle Image Velocimetry as well as pressure transducers and microphones to establish the experimental techniques needed to investigate the jet development stages, pressure and shear stress distributions on the plate, and the velocity and pressure oscillations on the plate. Upon completion of this project, the applicant laboratory will have the necessary facility to initiate a CRD project with ArcelorMittal (Dofasco) to develop the next generation wiping air knifes.

在连续热浸镀锌中，在钢板基材的每一侧上使用高速平面空气射流，称为“气刀”，以控制锌涂层的厚度。在移动的钢板浸入熔融锌浴中之后，这些射流对移动的钢板的冲击使得过量的熔融锌被擦回锌浴中。迄今为止，只有单槽喷嘴用于镀锌工业和其他热处理应用，如玻璃钢化、复杂表面加热、涡轮机叶片冷却和电子设备冷却。拟议的研究工作的目的是开发新的气刀几何形状组成的多个狭缝射流，它可以被设计成产生特定的和所需的组合的压力梯度和剪切应力分布的钢板，从而促进上级涂层重量控制的镀锌工艺参数范围广泛。使用多个狭缝喷嘴而不是单个喷嘴也有望减少钢带上的压力波动，这改善了涂层质量及其重量一致性，并减少了由气刀产生的噪音。进一步预期，使用多喷嘴技术将允许产生比目前使用单喷嘴技术可能产生的涂层重量更低的涂层重量，从而克服目前单喷嘴技术的这种限制。该参与提案涉及该项目的第一阶段，所要求的资金将用于建立多槽喷气设施和测量技术。设计、制造和调试了一台多缝射流冲击平板的多功能试验装置。这一初始阶段还将包括激光多普勒测速仪和粒子图像测速仪以及压力传感器和麦克风的密集使用，以建立所需的实验技术，以研究射流发展阶段，板上的压力和剪切应力分布，以及板上的速度和压力振荡。本项目完成后，申请实验室将拥有必要的设施，与ArcelorMittal（Dofasco）一起启动CRD项目，以开发下一代擦拭气刀。