Similarity Of Aeroelastic Model Of Tensile Membrane Structure

In the aeroelastic model test of tensile membrane structures,test conditions and membrane limits cause that the scaled model may not meet the requirements of similarity ratio.When the deviations in similarity exist,there is a doubt that the model can be used to reflect the prototype.Previous studies on similarity are mostly qualitative and lack quantitative analysis.Therefore,it is necessary to study the influence of the deviations on structural response through a large number of parameter analyses.The similarity design and compensation proposals are also necessary.In this paper,the similarity researches on tensile membrane structure are carried out.Several similarity criteria of tensile membrane structures are derived.The similarity deviation analyses of saddle and umbrella membrane structures are carried out.An aeroelastic model test of saddle membrane structure is used to verify the feasibility of similarity design methods and related compensation schemes.The main contents are as follows:(1)Dimensional analysis is used to derive the similarity criteria of aeroelastic model of tensile membrane structure.The similarity relationship between the scaled model and the prototype is analyzed respectively for the saddle and umbrella membrane structures.The vibration,static and dynamic analyses are carried out,and the deviations between the predicted response of prototype response and the prototype response are compared.The results show that the vibration and static results are similar,but the dynamic results are slightly deviation.(2)Through the sensitivity analysis,the effects of the deviations on the structural response are determined,and the unsatisfied similarity relations are compensated.Through the comparison of analysis results of saddle and umbrella membrane structure,the characteristics of the similarity of membrane structure are given.Research shows that the saddle aeroelastic model needs to consider the similarity criteria of membrane surface quality,tensile stiffness and Poisson ratio,and the umbrella aeroelastic model needs only to consider the similarity criteria of membrane surface quality and tensile stiffness.The similarity of the scaled model and the prototype can be realized by reasonable similarity design method and compensation scheme.(3)An aeroelastic model test of saddle membrane structure is carried out.The feasibility of similarity design method and relative compensation scheme are verified by comparing the prototype and two scale d models in the vibration,static and dynamic tests.The results show that the scaled model using similarity design method has similar vibration and static results but deflected dynamic results.For the scaled model which does not satisfy the prototype,the prediction accuracy is improved remarkably when the compensation scheme is adopted.