Particle Image Velocimetry (PIV) の基礎

抄録

Fundamentals of Particle Image Velocimetry (PIV) are introduced. The paper describes short historical story of the PIV. The origin of the word of the “PIV” is seen in the paper described by Adrian (1984). The PIV techniques are based on the flow visualization. The velocity measurement methods based on the flow visualization are also introduced. Particle Streak Velocimetry (PSV), Laser Speckle Velocimetry (LSV), Particle Tracking Velocimetry (PTV), and PIV have been used for flow velocity measurements. Differences among these methods are explained. Basic construction of PIV and timing chart of image acquisition are shown. While normal PIV used only one camera for measuring two-dimensional velocity components in a measurement plane, multiple cameras are used for extended measurements of three-dimensional velocity components. The concepts of the extended PIV is also explained. Several measurement results are introduced. Flow around a cylinder, flow around a car model, and in-cylinder flow are shown as basic results by PIV. Spray flow is shown as an example of a combination measurement of PIV and Laser Doppler Anemometry (LDA). Laser Induced Fluorescence (LIF) method presents a brightness distribution in the thin fluid film. The combination of LIF and PIV is applied to measure oil film behavior on the piston skirt in the model engine. These results by simple and complex measurement techniques are shown in last parts.