What is Particle Image Velocimetry?

Particle Image Velocimetry (PIV) is a non-intrusive optical technique that is used to measure fluid velocity. It is based on the principle of tracking the movement of small particles in a fluid that are illuminated by a laser sheet. By capturing the particles’ movement using high-speed cameras, the velocity field of the fluid can be calculated. PIV is commonly used in fluid dynamics research to study the flow of fluids in various applications such as aerospace, automotive, and biomedical engineering.

Principles of Particle Image Velocimetry

PIV works by capturing images of small particles that are suspended in a fluid. The particles are illuminated by a laser sheet, and the light scattered by the particles is captured by high-speed cameras. By comparing the positions of the particles in two successive images, the velocity of the fluid can be calculated. The accuracy of the velocity measurement depends on several factors, including the particle size, the camera resolution, and the laser sheet thickness. PIV can measure both the magnitude and direction of the fluid velocity.

Applications of Particle Image Velocimetry

PIV has a wide range of applications in various fields of engineering and science. In aerospace engineering, PIV can be used to study the flow of air around aircraft wings to optimize their design. In automotive engineering, PIV can help in the development of more aerodynamic car designs. In biomedical engineering, PIV is used to study blood flow and the movement of fluids in organs. PIV can also be used to study the dynamics of ocean currents and other natural phenomena.

Advantages and Limitations of Particle Image Velocimetry

One of the main advantages of PIV is that it is a non-intrusive technique, meaning that it does not disturb the flow of the fluid being studied. PIV also provides high spatial and temporal resolution, allowing for detailed analysis of fluid flow. However, PIV has some limitations, including the need for a high-quality laser source and the difficulty of capturing images in opaque fluids. PIV is also limited in its ability to measure very high velocities, as the particles may become displaced too quickly to be accurately tracked.