The Design Of Stage Separation And Grid Force Test In0.6m×0.6m Wind Tunnel

Stage separation and grid force test is one kind of technologies of wind tunnel test,simulate aircraft have two or more stages separating and measure aerodynamic load ofthe stages in interferential field. This technology is applied for designing aircraft haveseveral stages or external stores widely, provides test data for configuration of themother body, separate body and the whole, provides data for attitude control ofseparation. The wind tunnels lacks the capacity of stage separation and grid force test inthe range of mach number2.0～4.5in our country. In order to satisfy the need, thisthesisrealizesthe stage separation and grid force test in0.6m×0.6m wind tunnel, whichis applied on severalaircrafts.This thesis introduces the structure and performance of0.6m×0.6m wind tunnel,analyses the advantages and problems for establishing the test technology. The upperand nether mechanism is utilized to support mother model and separation modelindependently and respectively. The mother model takes back-support style, and theseparate mode takes trail-support style. The support devices designed newly satisfy thestrength and interference requirement. The special wallboards designed newly hasdifferent slots from the old, satisfy the motion-space requirement of mother model andseparate model. A servo motor, transmission gears and displacement sensor are fixed toupper mechanism, which realizes automation that makes the motion of mother modelmore effectual. Siemens’s802C base line is utilized as independent controller of thesupport mechanism of model, eases the burden of control computer of wind tunnel,realizes simultaneous motion of the mechanism in horizontal and vertical direction. Thecontrol program of test is optimized by adding position compensation which solves theproblem that the reference center of model do not coincide with the rolling center ofwind tunnel and grid-point circulation which realizesthe load measurement at differentposition of model to the flow. The signals of balance are filtered, magnified, insuringtest data nicety.In the end, the thesis introduces the methods of the test and data processing. Forthe sake of easy installation, model should be designed to two stages, and the size mustfollow the design criterion. When adjusting the fix angle, the position where the winghas the max size is appointed as roll angle reference, straight section is appointed asattack angle reference, this method can boost fixing precision. Self-created software transits grid points into special format that802C base line can identify, boosting the testefficiency. The result data includes load and aerodynamic coefficient of wind axissystem, body axis system, no-rolling body axis system.