Finite element studies on supersonic panel flutter under high thermal environment with arbitrary flow direction

Mukherjee, Somenath and Manjuprasad, M and Sakravarthini, Deepa S and Avinash, R (2008) Finite element studies on supersonic panel flutter under high thermal environment with arbitrary flow direction. In: Proceedings of the International Conference on Aerospace Science and Technology (INCAST 2008-058), 26-28 Jun 2008, Bangalore, India.

Full text available as:
[img] PDF
Download (1967Kb)

    Abstract

    Panels of re-entry vehicles are subjected to a wide range of flow conditions during ascent and re-entry phases. The flow can vary from subsonic continuum flow to hypersonic rarefied flow with wide ranging dynamic pressure and associated aerodynamic heating. One of the main design considerations is the assurance of safety against panel flutter under the flow conditions characterized by harsh thermal environment. This paper presents the work carried out at NAL to estimate the effects of a thermal profile in lowering the critical dynamic pressure (flutter boundary) of flat rectangular panels subjected to supersonic flow. A finite element formulation (employing the Kirchoff plate C1 bending element) has been developed here for supersonic flutter analysis of simply supported rectangular panels without in-plane edge constraints subjected to an assumed parabolic thermal profile that can result from any residual heat seeping into the metallic panels through the thermal protection systems. The piston theory is used for aerodynamic pressure computations, and provision is made to take into account the effect of arbitrary flow directions with respect to the panel edges. The results generated using the in-house finite element code and also the MSC NASTRAN software are in good agreement with analytical results. From the analysis of the results for various flow directions it has been observed that the flow along the longer side of any panel is most critical. It has been shown that for simply supported panels with no in-plane edge constraints, the thermal gradients (from the assumed parabolic profiles) can cause a drastic fall in the flutter boundary due to in-plane thermal stresses that effectively reduce structural stiffness. The present study will be useful for the purpose of panel design in re-entry launch vehicles and supersonic fighter aircrafts.

    Item Type: Conference or Workshop Item (Paper)
    Additional Information: Copyright for this article belongs to National Aerospace Laboratories
    Uncontrolled Keywords: Fighter aircraft;Supersonic panel flutter;Finite element method
    Subjects: AERONAUTICS > Aeronautics (General)
    Division/Department: Structures Division, Structures Division, Structures Division, Structures Division
    Depositing User: Ms. Alphones Mary
    Date Deposited: 06 Mar 2009
    Last Modified: 17 Jun 2010 14:33
    URI: http://nal-ir.nal.res.in/id/eprint/5008

    Actions (login required)

    View Item