Investigation on the Interference of Pre-bending Support Joint in Rotary Balance Test

Abstract

In order to get a wide range of angles of attack, pre-bending support joints are used in rotary balance test. The pre-bending support joint is located in the model wake region at low angle of attack. The pre-bending support joint can cause interference with aerodynamic force and aerodynamic moment of the model. Based on the FD-09 low speed wind tunnel rotary balance test system, the test is carried out by installing the pre-bending support joint at a symmetrical negative angle and rotating the model by 180 degrees. The test results show: that the aerodynamic characteristic of the SDM model are interfered by the pre-bending support joint, when the pre-bending support joint is located in the model wake region at low angle of attack. But the interference of pre-bending support joint mainly causes the translation of the aerodynamic characteristic curve, and the interference of pre-bending support joint is of little effect on the rotation derivative. The interference correction method proposed in this paper is very simple, which can provide a convenient and fast test method for the research of interference correction of the pre-bending support joint in rotary balance test.

Keywords

• low speed wind tunnel
• rotary balance
• low angle of attack
• pre-bending support joint
• interference