Development of Velocity Measurement Technology for Micro space with Curvature Wall

In order to establish a flow velocity measurement technique for a micro space with curvature on the wall, we selected a material with the same refractive index as water in order to suppress distortion caused by curvature distribution. We also adopted a lens to focus the micro space at an appropriate resolution. By combining these with a high-resolution camera, a double pulse laser, etc., we constructed a milli/micro-meter PIV system applicable to a field angle of 1 mm or more/less. As a result of measuring the flow velocity of water in a circular pipe of 10 mm to 100 μm in diameter, the flow velocity distribution agreed with the theoretical solution in the laminar flow case, and the flow velocity distribution agreed with the power law except near the wall in the turbulent flow case.