3-DIMENSIONAL MEASUREMENTS IN NON-AXISYMMETRICAL FLOW EXPERIMENT USING A ONE-COMPONENT OR 2-COMPONENT LASER-DOPPLER ANEMOMETER

A method to determine the velocity components in the third direction f or steady- non-axisymmetric nozzle flow experiments has been developed in addition to the two components that could be directly measured by a one- or two-component laser-Doppler anemometer. With the aid of this method, rotation for either the test rig or the anemometer become unn ecessary. Results obtained by this approach were used to compare with those directly measured in the downstream wake of a co-axial nozzle wi th a central five-lobe forced mixer where the flow is non-axisymmetric . Good agreement could be obtained with maximum discrepancy at about 5 %. The present approach can be readily applied to many other non-axisy mmetric nozzle flow situations with only some minor modifications.