Thrust Vector Control of an Overexpanded Supersonic Nozzle Using Pin Insertionand Rotating Airfoils

摘要

An experimental study of probe thrust vector control of overexpanded supersonicflow in nozzles using movable probes as the vectoring mechanism is presented. Two type of movable probes were used. The first inserted cylindrical proves through the wall of the nozzle to set depths relative to the nozzle wall; the second used rotating airfoils, inserted within the nozzle flow, rotated to various angles of attack relative to the nozzle centerline. Effectiveness of these probe thrust vector control mechanisms was investigated for a confined jet and conical nozzle. The study objective was to evaluate performance and transient characteristics of these probe thrust vector control mechanisms. Data are presented for both a confined jet nozzle and conical nozzle operating with primary stagnation pressures ranging from 150 psia to 460 psia and exhausting to atmospheric pressure. The range in pressure above 150 psia represents the region where flow in both configurations is stable and supersonic in axial operation. Limitations in the pressure supply allowed evaluation of both configurations only in the overexpanded flow regime. Axial force, lateral force, and static nozzle wall pressure distribution data were measured for axial and vectored operation for each nozzle configuration. Test results showed that probe thrust vector control using cylindrical pin insertion is a viable thrust vectoring mechanism. Performance of the cylindrical pins was repeatable in both nozzle configurations. Test results for the inserted airfoils showed that axial operation with inserted airfoils was not possible.