This is the next generation super-orbital expansion tube after X1. It is capable of operating at similar conditions to X1 but has a larger diameter (85 mm) facilitating larger models. The driver section in X2 has a compound piston allowing for a shorter compression tube than would be otherwise necessary.
The conditions to be expected in the flow assuming equilibrium are given in the following table:
|
Parameter
|
Moderate Enthalpy |
High Enthalpy (Nitrogen) |
| Free-stream |
Normal Shock |
Freestream |
Normal Shock |
|
Pressure (kPa)
|
67 |
1890 |
3.3 |
220 |
|
Temperature (K)
|
4900 |
8500 |
4800 |
11500 |
|
Density (kg/m3)
|
0.046 |
0.52 |
0.0022 |
0.030 |
|
Enthalpy (MJ/kg)
|
27 |
27 |
61 |
61 |
|
Velocity (km/s)
|
6.55 |
0.6 |
10.3 |
0.7 |
|
Mach Number
|
4.8 |
0.3 |
7.3 |
0.2 |
|
Diss. fraction N2
|
- |
0.47 |
0.06 |
1.0 |
|
Ion. fraction N
|
- |
- |
- |
0.06 |
Tim McIntyre
email: mcintyre@physics.uq.edu.au