Research in Engineering and Aviation

Examination of Three Dimensional Flow over a Chambered Inflatable Wing


Author(s): Zhang, F., K.J. Ghobadi,  R.P. LeBeau, and M. McQuillling

Examination of Three Dimensional Flow over a Chambered Inflatable Wing. Accepted to the 31st AIAA Applied Aerodynamics Conference, San Diego, CA.


Inflatable wings provide a compact alternative for aircraft that need to fit into small volumes before deployment, such as backpack unmanned aircraft or rocket-delivered air vehicles. Common inflatable designs use inflation chambers separated by spanwise baffles, generating a naturally undulating airfoil surface. Early wind tunnel tests of these designs showed evidence that separation over these airfoils was reduced compared to their smooth counterparts. Subsequent efforts to replicate these advantages computationally have proven ambiguous—while under certain conditions the inflatable airfoil may improve the lift-to-drag characteristics of the wing, in other conditions the inflatable profile appears detrimental. Recent PIV experiments on NACA 4318 inflatable and smooth airfoil models have provided an alternative view of these flows, but with the additional complication of three-dimensional flow effects and lack lift, drag, and pressure data. As such, the current effort is to expand the CFD to three-dimensional simulations. The initial targets of these comparisons are moderate Reynolds number (~105) flows.