An experimental investigation of the velocity and temperature fields of cold jets injected into a hot crossflow

It is shown here by dimensional analysis that the near-wall flow filed of an effusion-cooled combustor can be scaled if the Reynolds. Mach, and Prandtl numbers and the temperature and velocity ratios are kept constant. It is also demonstrated that a practical model experiment can be designed, which fulfills all the scaling laws. A test rig meeting these requirements has been designed built and tested The experimental conditions have been chosen to correspond to the conditions usually met in a real effusion-cooled combustion chamber. One geometric configuration has been investigated. This consists of one transverse row of holes drilled with a 30 deg angle to the wall through which the cooling air enters a cross-flowing mainstream, The mean values of ail three velocity components and the three normal fluctuating Reynolds stresses as well as the mean temperature have been measured in a large number of points surrounding the central injection hole. Experiments were carried out for jet-to-mainstream density ratios of 1.2 and 1.8. The results indicate that realistic density ratios are necessary to provide data directly applicable io effusion-cooling design.