3D Printing Technique for Experimental Modeling of Hydraulic Structures: Exemplary Scaled Weir Models

Abstract

3D printing is a fast growing industry and is affecting many areas of our daily lives, e.g., in medical fields, mechanics, as well as engineering. For hydraulic experimental modeling, this technique offers a new alternative that could enable a more sufficient and rapid model fabrication, especially for models that feature complex geometries. The present study thus evaluates the feasibility of applying 3D printing to fabricate scaled hydraulic experimental models for laboratory use. Various weir models were printed and compared to conventionally produced reference models in terms of the fabrication process, resulting discharge coefficients, and hydraulic performance. Results show that while being more cost- and time-effective during the fabrication process, properly 3D printed models were able to fulfill experimental requirements and deliver accurate results with a relative deviation less than 5% compared to conventionally fabricated models. The printing layer height was found to be the most critical parameter influencing the model’s final quality. Associated with the additive building approach, surface irregularities of 3D printed models were noted to be able to cause undesired nappe behavior, which might affect experimental results under certain conditions. To avoid such issues, a reduction of plotted layer heights or additional surface improvements could be helpful. Based on experimental results and visual assessments, 0.4 mm layer height can be recommended as a good compromise for model configurations tested herein.