Particulate fouling on structured surfaces is typically quantified using the integral thermal or mass-based fouling resistance. The observed geometries may be structures that can improve the heat transfer in heat exchangers (e.g., dimples), cavities in components, or more complex geometries. However, due to limited accessibility or the requirement for a locally resolved measurement, the existing quantification methods may not be applicable to structured surfaces. For this reason, a new method is needed for the quantification for fouling deposits. In this study, dimpled surfaces were evaluated by measuring the integral thermal and mass-based fouling resistance and comparing it with the local fouling resistance inside and around the dimple. This comparison was carried out online with the Phosphorescent Fouling Quantification method developed for this purpose, using phosphorescent particles to quantify the deposited mass. The mass-based fouling resistance can be calculated using computer-aided image analysis. The measurements for the evaluation were conducted on dimpled surfaces, which produced a characteristic fouling pattern. With the new method a reduced surface coverage from up to 33.3 % was observed, which led to lower fouling resistances downstream of the dimple compared to a plain surface. These results confirm earlier numerical and experimental findings, suggesting an advantage of dimpled surfaces over other surface structures with respect to thermo-hydraulic efficiency as well as reduced fouling. Thus, the Phosphorescent Fouling Quantification method provides the possibility of calculating values for local fouling resistances on structured surfaces, as well as the possibility of optimizing surface structures to minimize fouling propensity.

通常使用整体的基于热或基于质量的结垢阻力来量化结构化表面上的颗粒结垢。观察到的几何形状可以是可以改善热交换器（例如，凹坑）中的热传递，部件中的空腔或更复杂的几何形状的结构。但是，由于可访问性有限或需要进行本地解析的测量，因此现有的量化方法可能不适用于结构化表面。因此，需要一种新的方法来量化结垢沉积物。在这项研究中，通过测量整体的基于热和质量的结垢阻力并将其与凹坑内部和周围的局部结垢阻力进行比较，对凹坑表面进行了评估。该比较是使用为此目的开发的磷污垢定量方法在线进行的，该方法使用磷光颗粒对沉积的物质进行定量。可以使用计算机辅助图像分析来计算基于质量的耐污垢性。用于评估的测量是在有凹痕的表面上进行的，这会产生特征性的结垢图案。使用新方法后，观察到的表面覆盖率降低了33.3％，与平整表面相比，凹痕下游的结垢阻力降低了。这些结果证实了较早的数值和实验结果，表明就热工液压效率和减少的结垢而言，凹坑表面优于其他表面结构的优点。因此，