Compared with methods for measuring speed (LDA, HWA, PIV)
Study on the type of flow, to design and improve the mechanical systems necessary fluids. May in the new speed measurement tools, such as hot wire flowmeter Hot wire Anemometry, laser dog vane ( Laser Doppler Anemometry ) and the image of the particle image velocimetry poll particles more application of this study was trying to operating theory, applications, benefits and drawbacks. The three methods paid attention to the study conducted HWA method in places where it is appropriate to less heat and lower accuracy is concerned, as well as in places where there is less mobility (due to take pictures of successive) and cost less launch is considered the best method, PIV method is sensitive places and accurate and also of fluids and gases that have a high speed, the best way to assess could LDA that maintain speed.