FreeCASE - Free(dom) Computational AeroServoElasticity
 Sitemap Last update:January 15. 2016 14:05:15

### Oblique shock

In this section we present the numerical results of AeroFoam solver for a very simple 2D aerodynamic test problem, such as the reflection of an oblique shock.

#### Problem definition

• Domain:
• Rectangular channel of length L = 4.17 m and height h = 1 m
• Material:
• Polytropic Ideal Gas (PIG)
• Specific heat ratio gamma = 1.4
• Gas thermodynamic constant R = 287.05 J/kgK
• Initial conditions:
• Thermodynamic pressure Poo = 101325 Pa
• Temperature Too = 288.15 K
• Mach number Moo = 2.9
• Boundary conditions:
• SupersonicInlet boundary conditions on the inlet section (front and top walls)
• ExtrapolatedOutlet boundary conditions on the outlet section
• Slip boundary conditions on the bottom wall

Figure: Problem definition.

#### Space and time discretization

• Space discretization:
• Progressively refined meshes created with blockMesh
• # of rectangular cells Nv = 400 - 1600 - 6400 - 25600
• # of nodes Nn = 451 - 1701 - 6601 - 26001
• Time discretization:
• Total simulation time endTime = 0.01 s
• Timestep deltaT = 4e-5 - 2e-5 - 1e-5 - 5e-6 s
• Maximum Courant number maxCo =  1.95

Figure:
Computational grid.

#### Numerical results

• Comparison with exact solution and with OpenFOAM built-in inviscid compressible solvers rhoSonicFoam, rhopSonicFoam and sonicFoam
• Single iteration CPUtime = 8.16e-3 - 2.07 e-2 - 6.11e-2 - 2.22e-2 s on AMD64 3500+ desktop PC with AMD Athlon 64 2.2 GHz CPU, 1 Gbyte RAM, 512 Kbyte L2 cache

Figure:
Thermodynamic pressure P contours at t = 0.02.

Table: Comparison of the accuracy and efficiency performances of the evaluated solvers.

Figure:
Thermodynamic pressure P contours as a function of time t = 0 - 0.02.