| 摘要 |
FIELD: physics; test engineering. ^ SUBSTANCE: present invention pertains to experimental aerodynamics and can be used for determining damping properties of aeroplane models with propellers in air tunnels. The method involves testing a model aeroplane with propellers in a wind tunnel. A propeller, in form of a fan and gas turbine, is fitted onto the model. Compressed air is let into the turbine through a mast assembly and an intra-model rotary group, resulting in the propeller rotating at a speed necessary for simulating its operation. The damping properties of the model are determined using a "work" model, based on equation of the change in kinetic energy of the rotating flywheel for a single revolution and work done by aerodynamic forces and frictional forces in the rotary groups of the experimental assembly for a single period of oscillation of the model. Testing is carried out in oscillating mode of the model with constant amplitude and time varying frequency in the presence of an air stream in the wind tunnel. ^ EFFECT: increased accuracy of aerodynamic damping characteristics of aeroplane models with propellers, obtained in a wind tunnel due to simulation of operation of an engine-propeller power installation. ^ 1 dwg |
