Two-Dimensional Confined Jet Thrust Vector Control with Flow Visualization and Variable Flow Geometry

摘要

In this experimental investigation, the performance parameters considered were axial force, side force, and vector angle. Variables included primary pressure, exit-to-throat area ratio, and exit-to-throat axial length. With each test configuration, it was possible to define specific operating modes where the flow was oscillatory, vectored/switchable, and vectored/unswitchable. Only one test configuration yielded a stable axial flow on which secondary injection could be used to study vectoring. Switchable flows existed only at low pressure below the range of test pressures making it impossible to study switching characteristics. Because the flows were attached over the entire range of test pressures, geometric effects were based on the study of these attached flows. Results indicate that the theoretical equations for predicting wall separation points in unconfined nozzles do not accurately predict the separation points in confined jet nozzles. Small variations in axial length, as examined in this study, had a minimal impact on nozzle performance. Primary pressure and exit-to-throat area ratio have the most significant impact on two-dimensional nozzle performance. Keywords: Two dimensional flow; Flow visualization; Axial thrust. (Theses)