High order computational grids in CGNS format for the simulation of inviscid flow over a wing with an elliptic planform.

This is a set of high order computational grids for the simulation of inviscid flow over a wing with an elliptic planform. The wing has a span of 10 meter, a root chord length of 1 meter and consequently an aspect ratio Ar = 40/Pi. The profile of the wing is a symmetric NACA-0012 profile, hence zero lift is obtained for zero degree angle of attack. These grids are meant to be used in combination with a higher order finite element method (e.g Discontinuous Galerkin) to test how well the numerical discretization is able to predict the induced drag. Due to the large aspect ratio of the wing, lifting line theory can be used to predict the induced drag coefficient, CD_i, as a function of the lift coefficient CL, i.e. CD_i = CL^2/(Pi Ar). For the given aspect ratio of this wing this results in CD_i = 0.025*CL^2.<br>The following grids are available in CGNS format, version 4.5FullWingHexOnlyCoarse_P3.cgns: Cubic grid of the full wing that consists of 13,056 hexahedra (CGNS element type HEXA_64)FullWingHexOnlyMedium_P3.cgns: Cubic grid of the full wing that consists of 104,448 hexahedra (CGNS element type HEXA_64)FullWingHexOnlyCoarse_P4.cgns: Quartic grid of the full wing that consists of 13,056 hexahedra (CGNS element type HEXA_125)FullWingHexOnlyMedium_P4.cgns: Quartic grid of the full wing that consists of 104,448 hexahedra (CGNS element type HEXA_125)<br>The following grids are available in CGNS format, version 3.31HalfWingTetOnlyCoarse_P4.cgns: Quartic grid of half the wing that consists of 16,100 tetrahedra (CGNS element type TETRA_35)HalfWingTetOnlyFine_P4.cgns: Quartic grid of half the wing that consists of 1,567,956 tetrahedra (CGNS element type TETRA_35)

本数据集为一套高阶计算网格（high order computational grids），用于模拟椭圆平面机翼的无粘绕流（inviscid flow）。该机翼展长为10米，根弦长为1米，因此展弦比（aspect ratio, Ar）为40/π。其翼型为对称NACA-0012翼型（NACA-0012 profile），故在零攻角工况下升力为零。本套网格可配合高阶有限元方法（higher order finite element method，例如间断伽辽金方法（Discontinuous Galerkin））使用，用于验证数值离散格式对诱导阻力（induced drag）的预测精度。由于该机翼展弦比较大，可采用升力线理论（lifting line theory）根据升力系数（lift coefficient, CL）预测诱导阻力系数（induced drag coefficient, CD_i），即CD_i = CL²/(πAr)。针对本数据集给定的展弦比，可得CD_i = 0.025×CL²。

以下为CGNS格式（CGNS format）的网格文件，版本4.5：
FullWingHexOnlyCoarse_P3.cgns：全机翼三次网格，包含13056个六面体（CGNS单元类型HEXA_64）
FullWingHexOnlyMedium_P3.cgns：全机翼三次网格，包含104448个六面体（CGNS单元类型HEXA_64）
FullWingHexOnlyCoarse_P4.cgns：全机翼四次网格，包含13056个六面体（CGNS单元类型HEXA_125）
FullWingHexOnlyMedium_P4.cgns：全机翼四次网格，包含104448个六面体（CGNS单元类型HEXA_125）

以下为CGNS格式的网格文件，版本3.31：
HalfWingTetOnlyCoarse_P4.cgns：半机翼四次网格，包含16100个四面体（CGNS单元类型TETRA_35）
HalfWingTetOnlyFine_P4.cgns：半机翼四次网格，包含1567956个四面体（CGNS单元类型TETRA_35）