What is a velocimeter?
velocimeter is a device used to measure fluid and gases. Some velocimeters measure particle movements that have been suspended in liquid, while others use only reflected lasers. A study of fluid and gases is called velocimetry.
The velocimeter can be used to measure two different types of fluid dynamics. The "Lagrang's flow field specification" is when the particles are dropped into the liquid and their movements are observed. It is similar to watching a wand transmitted by a current or caught in a whirlpool. "Eulerian specification of the flow field" observes a specific point in flow for a certain period of time. It is analogous to sit on the shore and watch one bend of the river.
The particle velocimetry is in the water inserting into the water and measuring their speed. The particles can be small droplets of water or oil or pellets of metal and glass. The velocimeter measures the speed of these Particles by photographing is at one point of their movement in the stream. Then another photo is timed that will be taken by a fewmoments later. Both photos will be compared and the total fluid speed will be determined.
The camera used to take photos of particles is a laser beam. Dvě čočky se zplošťují a rozšířují paprsek, aby vytvořily krátký záblesk, který je poté analyzován za účelem vytvoření dvourozměrného nebo 2D obrazu. Lasers are used because the particles are fast moving and microscopic. The normal camera lens cannot open and close fast enough to capture their movements.
Another type of velocimeter is called Doppler Velocimeter. In this type of velocimetry, light reflections are measured instead of particles. Velocimetr řídí například laserový paprsek na pacientovy tepny a způsob, jakým světlo odráží pohyblivou krev, řekne technikovi, jakkrev cirkuluje. This type of measurement is based on the Doppler effect, when the speed of light can be assessed by measuring the wool frequency relative to the observer.
Velocimetry has many practical applications. The velocimeter can determine the "swirling" of gases and fluids in internal combustion engines, furnaces, drying and chemical processing plants. Knowing how fluids move in machines helps designers plan to wear and diagnose problems and overall practicality of the system. Since laser velocimetry is non -invasive, it can also be used as part of medical procedures.