Team for Advanced Flow Simulation and Modeling

For more information:
tezduyar@gmail.com

Fluid Mesh - Solid Propellant Cases

This case was run on a fluid mesh that surrounds a single cylindrical solid propellant. Figure 1 shows a cross section of this mesh where the white rectangles represent the propellant. The large white area in the middle of the figure 1 is the projectile. The propellant in this problem was deformable and free to move.

No-slip boundary conditions were imposed on the propellant surface, the projectile surface, and the outer and right boundaries. The pressure and temperature were imposed on the left boundary. The pressure profile was introduced across the entire left boundary for 1600 time steps of 1.0e-5 seconds. Figure 2 shows the pressure contours of the first time step. Figure 3 shows a color bar of the pressures. The pressure within the computational domain for a given time step is very tightly grouped relative to the maximum and minimum of the pressure introduced on the left boundary. Therefore, the highest and lowest pressure for each time step is assigned to the maximum and minimum values of the color map.

Figure 1 Figure 2
Figure 3

The result was pressure waves oscillating along the length of the computational domain. An interesting observation was that the pressure distributions on the inside and outside surfaces of the propellant differ rather significantly. This is shown in figure 4. The results from the solid cases show that the solid propellant compresses or expands dramatically for a relatively small difference in pressure across its boundaries.

Figure 4

Portions of the run can be viewed with the movies below.

Fluid Mesh Movie with Time Steps = 1 - 300

Fluid Mesh Movie with Time Steps = 501 - 800

Fluid Mesh Movie with Time Steps = 801 - 1100