In order to finely and continuously adjust the damping of a spring-suspended sectional model (SSSM) system in the wind tunnel test,a double-sided permanent magnet plate-type eddy current damper (ECD) device is developed in this paper. First,the basic structure of the ECD is introduced and its design points are analyzed. Then,the rationality of the structure for the ECD is analyzed by using the electromagnetic finite element steady-state analysis method,its working range is predicted,and the influence of the motion speed and position offset of the conductor plate on its working performance is analyzed. Finally,the relationship between the vertical and torsional additional damping ratio provided by the ECD to the SSSM system is derived,and the linear characteristics of the eddy current damping and the cooperative adjustment ability of the damper to the vertical and torsional additional damping of the SSSM system are verified by experiments. The study shows that the double-sided permanent magnet plate-type ECD can provide continuously adjustable linear viscous damping for the SSSM system with different scaling ratios,and the damping coefficient is stable and not easily affected by the front-back,left-right and up-down position offsets of the model,which is also suitable for the wind tunnel test of the SSSM system with large bending-torsional coupling vibration. By installing two dampers symmetrically along the diagonal of the SSSM system,the vertical and torsional damping ratios of the SSSM system can be cooperatively adjusted,which provides conditions for the fine study of the bending-torsional coupling wind-induced vibration of the SSSM system.
| 科 Family | 属数 Number of genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) | 属 Genus | 种数 Number of species | 占总种数比例 Percentage of total species (%) |
|---|---|---|---|---|---|---|
| 鹅膏菌科Amanitaceae | 2 | 11 | 5.26 | 鹅膏菌属 Amanita | 10 | 4.78 |
| 小菇科 Mycenaceae | 2 | 12 | 5.74 | 丝盖伞属 Inocybe | 5 | 2.39 |
| 多孔菌科 Polyporaceae | 8 | 14 | 6.70 | 蜡蘑属 Laccaria | 5 | 2.39 |
| 红菇科 Russulaceae | 3 | 23 | 11.00 | 小皮伞属 Marasmius | 6 | 2.87 |
| 小菇属 Mycena | 11 | 5.26 | ||||
| 光柄菇属 Pluteus | 5 | 2.39 | ||||
| 红菇属 Russula | 17 | 8.13 | ||||
| 栓菌属 Trametes | 5 | 2.39 |