1PIV Flow Field Measurements in a Rotating U-Shaped Channel. Comparison of smooth and 90 ° rib-roughened walls.

This paper presents our latest efforts in an ongoing program to improve the understanding of aerodynamic and thermal phenomena of internal blade cooling by forced convection and to incorporate this knowledge into predictive tools. The particular objectives of this program are to estimate the use of the 2D Particle Image Velocimetry technique and to produce experimental data obtained for various boundary conditions in order to anchor a computer code being developed in parallel. In this paper we compare the results of the investigations of the flow in two different configurations of the channel: 1) smooth internal walls, 2) internal walls of only one branch equipped with square profile ribs inclined at 90 ° to the main flow and placed on opposite walls (trailing and leading surfaces when in rotation). The test channel which consists in two radial branches connected by a 180 ° bend, rotates in orthogona