Flow Measurements Using Particle Image Velocimetry in the Ultra Compact Combustor

摘要

Velocity measurements were performed using the Particle Image Velocimetry (PIV) technique on the Ultra Compact Combustor (UCC) test rig at the Air Force Institute of Technology (AFIT). Velocity patterns and time- averaged turbulence statistics were calculated for data taken with the UCC burning hydrogen fuel in the straight cavity vane and curved cavity vane configurations. The equivalence was varied from 0.7 to 1.5, while the ratio of cavity air to main air was varied from 5% to 20%. Spanwise turbulence intensity penetrated into less than 50% of the main channel for all conditions except the richest (equivalence ratio of 1.5). A study was performed with the curved and straight sections increasing flow rates while holding other factors constant to determine velocity dependence. Relative turbulence intensities were independent of overall flow velocity in the straight configuration, while a negative correlation was observed in the curved configuration. Overall turbulence intensity levels were measured at 15% and 21% for the straight and curved configurations respective. The RVC generated significant flow rotation. Peak vorticity was observed farthest from the cavity vane suggesting the angle of the RVC is effective in generating increasing flow rotation with streamwise velocity.