Effects of Number of Stores on the Transonic Flutter Characteristics of a Delta Wing Configuration

Transonic and supersonic flutter characteristics of a delta wing configuration with external stores are simulated using the fluid/structure coupling method and the effect of the store aerodynamics is investigated. A delta wing with one and two external stores are considered in this study. The stores are located in the rearward of the wing simulating typical high speed aircraft configurations. The computational result shows that the flutter dynamic pressures over all the Mach numbers are reduced by adding external stores for both cases. In addition, the flutter dynamic pressures become much lower when the number of attached external stores is increased. In the case of the single external store, influence of the store aerodynamics can be divided into two regions according to the Mach number. It is found that neglecting the store aerodynamics leads to the overestimation of the flutter dynamic pressures in the supersonic region. In case of two external stores, the store aerodynamics influence on the flutter boundary only at M∞ =1 .22 unlike the case of the single external store. It is shown that the shock wave ahead of the external store influences on the pressure distributions on the lower surface and the location of the shock wave is important for the decision of the flutter boundary.

[1]  Eiji Shima,et al.  Role of CFD in aeronautical engineering. No. 14: AUSM type upwind schemes , 1997 .

[2]  Yoshiaki Tamura,et al.  Conservation law for moving and transformed grids , 1993 .

[3]  H. Lomax,et al.  Thin-layer approximation and algebraic model for separated turbulent flows , 1978 .

[4]  K. S. Nagaraja,et al.  Flutter study of an advanced composite wing with external stores , 1987 .

[5]  S. R. Chakravarthy,et al.  Relaxation methods for unfactored implicit upwind schemes , 1984 .

[6]  Scott A. Morton,et al.  Implementation of a fully-implicit, aeroelastic Navier-Stokes solver , 1997 .

[7]  Robert V. Doggett,et al.  Low-speed flutter characteristics of some simple low-aspect-ratio delta-wing models , 1992 .

[8]  Guru P. Guruswamy,et al.  A Parallel Multiblock Mesh Movement Scheme For Complex Aeroelastic Applications , 2001 .

[9]  Liviu Librescu,et al.  Static and Dynamic Aeroelasticity of Advanced Aircraft Wings Carrying External Stores , 1998 .

[10]  A. Jameson,et al.  Lower-upper Symmetric-Gauss-Seidel method for the Euler and Navier-Stokes equations , 1988 .

[11]  Robert V. Doggett,et al.  Experimental transonic flutter characteristics of two 72 deg-sweep delta-wing models , 1989 .

[12]  George W Jones.  Transonic flutter investigation of a 64 degree delta wing constructed with spars along constant-percent chord lines and streamwise ribs , 1957 .

[13]  R. H. Ricketts,et al.  Some experimental and theoretical flutter characteristics of an arrow-wing configuration , 1977 .

[14]  C. D. Turner.  Effect of Store Aerodynamics on Wing/Store Flutter , 1982 .

[15]  S. Obayashi,et al.  Aileron Buzz Simulation Using an Implicit Multiblock Aeroelastic Solver , 2003 .

[16]  R. N. Desmarais,et al.  Interpolation using surface splines. , 1972 .

[17]  Rakesh K. Kapania,et al.  Computational Fluid Dynamics/Computational Structural Dynamics Interaction Methodology for Aircraft Wings , 1998 .

[18]  W. Keats Wilkie,et al.  Experimental transonic flutter characteristics of supersonic cruise configurations , 1990 .

[19]  Raymond E. Gordnier,et al.  Transonic flutter simulations using an implicit aeroelastic solver , 2000 .

[20]  Kozo Fujii,et al.  Unified zonal method based on the fortified solution algorithm , 1992 .