Juliana Dorn Nóbrega, Harry Edmar Schulz,
André Luiz Andrade Simões, Rodrigo de Melo Porto
André Luiz Andrade Simões, Rodrigo de Melo Porto
Abstract. The sudden transition from supercritical to subcritical regimes in channel flows is known as hydraulic jump. Some geometrical characteristics of the transition such as the length of the roller and of the jump itself can be associated to turbulence parameters in different positions of the flow. These are generally obtained from the fields of mean and fluctuating velocities, being usually: turbulence intensity, Reynolds stresses, and turbulent kinetic energy. The techniques commonly used to determine the velocity fields are: hot-film anemometry, particle image velocimetry, laser Doppler velocimetry, acoustic Doppler velocimetry, acoustic displacement measurements. The aim of the present study is to compare different methods, in order to verify the adequacy of the ultrasonic sensor to predict the mentioned lengths of the hydraulic jump and the roller. The study considers experimental data found in the literature. In particular, the ultrasonic sensor measures the position of the water surface, and previous studies indicate that the variation of this position can be used to study the macroturbulence characteristics. The ultrasonic meter presents the positive aspects of being a robust technique, relatively easy to use, and less expensive than the alternative methods. The results of the present study point to the adequacy of using ultrasonic meters for measurements in hydraulic jumps.
Keywords: hydraulic jump, length of the roller, length of hydraulic jump, free-surface position.
Download22nd International Congress of Mechanical Engineering (COBEM 2013)
November 3-7, 2013, RibeirãoPreto, SP, Brazil
Copyright © 2013 by ABCM
