No abstract

No abstract

An argon ion laser velocimeter (LV) with four beams has been used to measure the detailed flowfield of an advanced eight blade propeller with 4S· of tip sweep in the Lewis 8x6 Foot Supersonic Wind Tunnel. The propeller was tested at a Mach number of 0.8. The propeller operated at an advance ratio of 3.06 and a blade angle at the three-fourths radius of 60.5·. The test configuration was also analyzed using a curved lifting line analysis. A comparison of analysis results with LV data indicated blade blockage occurred near the nacelle. This resulted in a deceleration ahead of the blade and unsteady flow downstream. The LV data also indicated the presence of a shock wave emanating from the suction surface at a radius ratio of 0.79. The curved lifting line analysis qualitatively predicted the SR-3 propeller flow field. The comparison showed some differences between prediction and LV measurements. These aifferences can be attributed to phenomena not included in tne analysis such as viscous blade wakes, tip vortex rollup, blade blockage, and nacelle effects. Tne comparison has indicated underpredictions in the magnitude of the radial velocity jump across the blade. These differences lead to differences in blade loading and wake location. advance ratio, Vo/nD Mach number rotational speed, revolutions per second power, kW (ft-lb/sec) radius, cm (in.) blade tip radius, cm (in.) free-stream velOCity, m/sec (ft/sec) tip rotational velocity, m/sec (ft/sec) axial distance from nose of spinner, cm (in. ) ratio of total temperature to standard sea-level temperature of 518.7· R free-stream density, kg/m 3 (slugs/ft 3 )

SummaryNon-intrusive measurements of velocit y about a spinner-propellernacelle configuration at a Mach number of 0.8 have been performed. A laser velocimeter., s p ecifically develcoed for these measurements in the NASA Lewis 8-by 6-foot Supersonic Wind Tunnel, was used to measure the flow-field of the advanced swept SR-3 prooeller. The laser velocimetPr uses an ar g on ion laser and a 2-color optics system to allow simultaneous measurements of ')-comoonents of velocity. The axisvmmetric nature of the propeller-nacelle flow-field permits two separate 2-dimensional measurements to be combined into 3-dimensional velocity data. Presented are data ahead of and behind the propeller bladef-and also a limited set in between the blades. As p ects of the observed flow-field such as the tip vortex are discussed.

An experimental investigation of a full scale mixed compression inlet sized for the TF30-P-3 turbofan engine was conducted at Mach 2.5 and 2.0 operating conditions. The two cone axisymmetric inlet had minimum internal contraction consistent with high total pressure recovery and low cowl drag. A t Mach 2.5, inlet recovery exceeded 0.90 with only 0.02 centerbody bleed mass-flow ratio and zero cowl bleed. A centerbody bleed of approximately 0.05 gave a maximum inlet unstart angle-of-attack of 6.85'.Inlet performance and angle-of-attack tolerance is presented for operation at Mach 2.5 and 2.0.