Simultaneous measurement of three velocity components and static pressure in turbulent flows

A new probe for the simultaneous measurement of three velocity components and static pressure in turbulent flows is developed and its measurement accuracy is checked. The probe consists of two X-type hot-wire probes and a static pressure probe that is placed at the center of hot-wires. The static pressure tube is manufactured by using a micro fabricated metal tube and drill to improve the spatial resolution. The external diameter of the static pressure tube is 0.3 mm and its internal diameter is 0.2 mm with 8 static holes on the wall of the tube. The measurement error in the pressure measurement caused by the cross-flow is compensated by the measured instantaneous three velocity components by two X-type hot-wire probes. The measurement results show that the cross-stream wise profile of the mean velocity, RMS value of the fluctuating three velocity components, and RMS value of the fluctuating pressure in a plane jet agree with those obtained in the previous studies. Further, it is also found that the profile of the production term and diffusion term in the turbulent energy transport equation which is directly estimated by the measured data is more improved than our previous studies. This is due to the improvement of the spatial resolution of the combined probe and the measurement accuracy of the velocity-kinematic energy correlation by the measurement of all three velocity components. ©2013 The Japan Society of Mechanical Engineers.