Small Scale Model Tests in Small Wind and Water Tunnels at High Incidence and Pitch Rates. Volume 2. Small Wind Tunnel (ADF) Data Base

Abstract : Force testing of small-scale models in either a small wind tunnel or a water tunnel was investigated as an inexpensive and quick means to obtain meaningful dynamic force and moment data representative of rapidly maneuvering full-scale aircraft. Force tests of flat-plate semi-span models were conducted in the General Dynamics Aerodynamic Development Facility (ADF) which is a small 14-in. x 14-in. low speed wind tunnel. Oscillatory model motions up to 48 deg (peak to peak) amplitude were tested at frequencies of 1 to 3 Hz. Force tests of flat and three-dimensional full span models were conducted in G.D.'s Hydroflow Facility (HFF) which is a horizontal flow water tunnel with a 24-in. x 24-in. test section. Pitch/pulse model motions were tested for conditions similar to those tested in the ADF. The test velocities were 100 fps in the ADF and 0.8 fps in the HFF which yielded nominal Reynolds numbers of 0.6 million and 0.06 million respectively (based on root chord). This volume presents the data base generated from tests in the ADF. The normal force, pitching moment and rolling moment data are in plotted and tabulated form for the straked wing, 55 deg and 70 deg delta wings and 70 deg/30 deg cranked wing semi-span models. Steady results along with unsteady results for two frequencies are included for the overall incidence range of 0 deg to 80 deg. Geometric data for the models are also given. Keywords: Aerodynamic forces, Unsteady flow, Vortices, Flat plate models, Wind tunnel tests.