Refined Tetrahedral Meshes with Mach Cone Aligned Prisms for Sonic Boom Analysis

A tetrahedral mesh generation method for acquiring accurate sonic boom pressure signatures several body lengths from an aircraft model has been developed. The method serves as a tool for aerodynamicists to efficiently create useful meshes for sonic boom analysis. The procedure includes generating a refined near-field grid with a cylindrically shaped boundary that encompasses the model just beyond its surface and a prismatic mesh from the cylindrical boundary to the far field. Projecting the boundary in the radial direction and forming prisms between neighboring layer faces creates the prism mesh. Each prism is subdivided into three tetrahedra resulting in a mesh comprised entirely of tetrahedral cells. The prism structure permits radial stretching and mesh alignment with the Mach cone around the aircraft model for accurate on- and offtrack signatures. Computational results for four models compared with experimental data validate this methodology.

[1]  Michael J. Aftosmis,et al.  Adjoint Error Estimation and Adaptive Refinement for Embedded-Boundary Cartesian Meshes , 2007 .

[2]  Donald Howe.  Hybrid CART3D/OVERFLOW Near-Field Analysis of a Low Boom Configuration with Wind Tunnel Comparisons (Invited) , 2011 .

[3]  Marie-Gabrielle Vallet,et al.  How to Subdivide Pyramids, Prisms, and Hexahedra into Tetrahedra , 1999, IMR.

[4]  C. M. Darden,et al.  Sonic-boom minimization with nose-bluntness relaxation , 1979 .

[5]  Mark S. Shephard,et al.  Boundary layer mesh generation for viscous flow simulations , 2000 .

[6]  Raymond M. Hicks,et al.  AERODYNAMIC SHAPE OPTIMIZATION USING UNSTRUCTURED GRID METHODS , 2002 .

[7]  Kelly R. Laflin,et al.  A Hybrid Computational Fluid Dynamics Procedure for Sonic Boom Prediction , 2006 .

[8]  Juliet Page,et al.  An efficient method for incorporating computational fluid dynamics into sonic boom prediction , 1991 .

[9]  Karen A. Deere,et al.  Efficient Unstructured Grid Adaptation Methods for Sonic Boom Prediction , 2008 .

[10]  T. Baker.  Automatic mesh generation for complex three-dimensional regions using a constrained Delaunay triangulation , 1989, Engineering with Computers.

[11]  N. Frink.  Assessment of an Unstructured-Grid Method for Predicting 3-D Turbulent Viscous Flows , 1996 .

[12]  C. M. Darden,et al.  CFD prediction of the near-field sonic boom environment for two low boom HSCT configurations. [High Speed Civil Transport] , 1991 .

[13]  Mathias Wintzer,et al.  Adjoint-Based Adaptive Mesh Refinement for Complex Geometries , 2008 .

[14]  Richard L. Campbell,et al.  Evaluation of Refined Tetrahedral Meshes with Projected, Stretched, and Sheared Prism Layers for Sonic Boom Analysis (Invited) , 2011 .

[15]  Peter G. Coen,et al.  A Performance Assessment of Eight Low-Boom High-Speed Civil Transport Concepts , 1999 .

[16]  Elizabeth M. Lee-Rausch,et al.  Application of Parallel Adjoint-Based Error Estimation and Anisotropic Grid Adaptation for Three-Dimensional Aerospace Configurations , 2005 .

[17]  Kenrick Waithe,et al.  Application of USM3D for Sonic Boom Prediction by Utilizing a Hybrid Procedure , 2008 .

[18]  Frédéric Alauzet,et al.  Fully anisotropic goal-oriented mesh adaptation for 3D steady Euler equations , 2010, J. Comput. Phys..

[19]  Michael J. Aftosmis,et al.  Adjoint-based low-boom design with Cart3D (Invited) , 2011 .

[20]  Susan E. Cliff,et al.  Near Field Sonic Boom Test on Two Low-Boom Configurations Using Multiple Measurement Techniques at NASA Ames (Invited) , 2011 .

[21]  A. R. George,et al.  Sonic Boom Minimization Including Both Front and Rear Shocks , 1971 .

[22]  Shahyar Pirzadeh,et al.  Advanced Unstructured Grid Generation for Complex Aerodynamics Applications , 2008 .

[23]  Scott L. Lawrence,et al.  Application of CFD to sonic boom near and mid flow-field prediction , 1990 .

[24]  Jeffrey A. Housman,et al.  LAVA Simulations for the First AIAA Sonic Boom Prediction Workshop , 2014 .

[25]  Kenrick Waithe,et al.  Design of a Wind Tunnel Mount for a Low Boom Test (Invited) , 2011 .

[26]  Michael D. Madson.  Sonic boom predictions for three generic models using a solution-adaptive full-potential code , 1991 .

[27]  Paresh Parikh,et al.  The NASA tetrahedral unstructured software system (TetrUSS) , 2000, The Aeronautical Journal (1968).

[28]  A. Jameson,et al.  Improvements to the aircraft Euler method , 1987 .

[29]  Eric J. Nielsen,et al.  Validation of 3D Adjoint Based Error Estimation and Mesh Adaptation for Sonic Boom Prediction , 2006 .

[30]  Michael Park,et al.  Low Boom Configuration Analysis with FUN3D Adjoint Simulation Framework (Invited) , 2011 .

[31]  Seongim Choi,et al.  Numerical and Mesh Resolution Requirements for Accurate Sonic Boom Prediction , 2009 .

[32]  Michael J. Aftosmis,et al.  Multilevel Error Estimation and Adaptive h-Refinement for Cartesian Meshes with Embedded Boundaries , 2002 .

[33]  Karen A. Deere,et al.  A Grid Sourcing and Adaptation Study Using Unstructured Grids for Supersonic Boom Prediction , 2008 .

[34]  Scott D. Thomas,et al.  Euler/experiment correlations of sonic boom pressure signatures , 1991 .

[35]  James E. Murray,et al.  Airborne Shaped Sonic Boom Demonstration Pressure Measurements with Computational Fluid Dynamics Comparisons , 2005 .

[36]  Michael J. Aftosmis,et al.  Sonic Boom Computations for a Mach 1.6 Cruise Low Boom Configuration and Comparisons with Wind Tunnel Data , 2011 .

[37]  Mathias Wintzer,et al.  Adjoint-based adaptive mesh refinement for sonic boom prediction , 2008 .