Experimental investigation of problems of fluid-solid interactions, involving difference air-/waterborne vehicles require access to both boundary layers and the far-field flow around the body. However, a conventional particle image velocimetry measurement is either restricted to low resolution access to the entire flow field, or a high resolution access to a limited portion of the body. In addition, access to the surreounding of opaque and non-trasparent samples will always be limited by shadow areas.

To respond to this challange, we have developed a multi-light sheet strategy to access the flow field all around an opque body. For slender samples, we use double-light sheet illumination strategy to access both side of a sample.

To access the details of larger bodies and hard-to-reach areas inside arrays of obstrcutive objects we use a quad-sheet strategy to illuminate the details of the flow.

To have high resolution access to the flow details in both near and far-field, we perform experiments at high-magnification and repeat the experiments in consecutive-overlapping steps to cover a large area of interest, larger than the field-of-view of the camera. We use a Computer Numiercally Controlled rail to control the location of the camera and based of that location we are able to stitch the results back together to get the full view.

More details on the technique are available at:

• Shuangjiu Fu, Prasoon Suchandra, and Shabnam Raayai-Ardakani. “Multi-sheet illumination and consecutive overlapping 2D-2C PIV acquisition for enhanced access to boundary layer flows around obstructive opaque objects.” In 15th International Symposium on Particle Image Velocimetry. San Diego, CA: San Diego State University, 2023.
• Shuangjiu Fu and Shabnam Raayai-Ardakani. “Double-light-sheet, Consecutive-overlapping Particle Image Velocimetry for the Study of Boundary Layers past Opaque Objects” Experiments in Fluids, 2023, 64(11):182.