Increasing the energy efficiency of plasma spraying by means of simulation-based process development

通过基于模拟的工艺开发提高等离子喷涂的能源效率

• 批准号: 442323795
• 负责人: Professorin Dr.-Ing. Kirsten Bobzin
• 金额: --
• 依托单位: Institut für Oberflächentechnik (IOT)
• 依托单位国家: 德国
• 项目类别: Research Grants
• 财政年份: 2020
• 资助国家: 德国
• 起止时间: 2019-12-31 至 2023-12-31
• 项目状态: 已结题
• 来源: https://gepris.dfg.de/gepris/projekt/442323795?language=en
• 关键词: Increasing; energy; efficiency; plasma; spraying

Plasma spraying is one of the most important process variants in thermal spraying. At present, only a small part of the available energy is used to accelerate and melt the particles. A promising solution for increasing energy efficiency is a solid shroud that surrounds the plasma free jet and thus prevents mixing with the ambient air. As a result of this separation, the plasma temperature can be increased, thereby raising the energy efficiency. Another expected positive effect is the prevention of oxidation of the spray particles and thus the coatings.The primary goal of the project is to investigate the potential to increasing the energy efficiency of the plasma spraying process by using a solid shroud. In this project a methodology will be developed to design such a shroud and to optimize its geometry for given process parameters. Ideally, this solid shroud also increases the plasma stability of the plasma jet and thus the process stability. Therefore, a further goal is to investigate the effects of a solid shroud on the plasma stability. In addition to energy efficiency, a solid shroud also offers great potential for improving coating properties. Consequently, the possible influence on the coating properties will be investigated. In order to achieve these goals, a numerical simulation model of a plasma generator with a solid shroud will be developed based on a model of previous DFG projects. By using modern algorithms, such as particle swarm optimization and evolutionary algorithms, the geometry of the solid shroud is then calculated and optimized. The effects of the nozzle extension on plasma stability will be investigated by high-speed videography of the plasma free jet and high-resolution current and potential measurements. For these, appropriate measuring equipment is requested as part of this proposal. In experimental tests the effect on the energy efficiency and on the coating properties will be determined for the spray materials Al2O3 and MCrAlY.In the third year of the research project, a further approach to increasing energy efficiency, preheating of the spray particles, will be investigated. By exploiting the radiation of the plasma jet, the particles can be preheated without the need for an external source of energy. With the help of numerical simulations and experiments, such a preheating device will be designed and its potential to increase the energy efficiency will be determined. A combination of a solid shroud and a particle preheating will also be examined in detail this third year.

等离子喷涂是热喷涂中最重要的工艺变量之一。目前，只有一小部分可用能量用于加速和熔化粒子。提高能源效率的一个有希望的解决方案是在等离子体自由喷流周围覆盖一层固体遮盖物，从而防止与环境空气混合。作为这种分离的结果，可以提高等离子体温度，从而提高能量效率。另一个预期的积极效果是防止喷雾颗粒的氧化，从而防止涂层的氧化。该项目的主要目标是研究通过使用固体裹尸布来提高等离子喷涂过程的能效的潜力。在这个项目中，将开发一种方法来设计这样的裹尸布，并根据给定的工艺参数优化其几何形状。理想情况下，这种固体护罩还可以提高等离子射流的等离子体稳定性，从而提高工艺稳定性。因此，进一步的目标是研究固体裹尸布对等离子体稳定性的影响。除了能源效率外，实心护罩还具有提高涂层性能的巨大潜力。因此，将研究可能对涂层性能的影响。为了实现这些目标，将在以前DFG项目的模型的基础上开发具有实心护罩的等离子体发生器的数值模拟模型。通过使用粒子群优化和进化算法等现代算法，计算和优化了实体裹尸布的几何形状。喷嘴延伸对等离子体稳定性的影响将通过对等离子体自由射流的高速摄像和高分辨率的电流和电位测量来研究。对于这些，作为本提案的一部分，需要适当的测量设备。在实验测试中，将确定喷涂材料Al_2O_3和MCrAl_Y对能效和涂层性能的影响。在研究项目的第三年，将进一步研究提高能效的方法--预热喷涂颗粒。通过利用等离子体喷射的辐射，粒子可以在不需要外部能源的情况下进行预热。在数值模拟和实验的帮助下，将设计这样的预热装置，并确定其提高能效的潜力。固体裹尸布和粒子预热的组合也将在今年第三年详细研究。