TITLE : UNDEREXPANDED FREE JET
BY : Q Zhang - CHAM Development Team
PHOENICS VERSION: 2.1 DATE: SEPTEMBER 1995
- The problem considered is an axisymmetric sonic jet
discharging into stagnant surroundings at a pressure
higher than the ambient pressure.
- The simulations are based on experiments of Donaldson
and Snedeker (1971).
- The simulation is two-dimensional and the k-e turbulence
model is used.
Pictures are as follows :
1. Pressure contours
2. Mach number contours
3. Density contours
4. Mach number distribution along the flow axis
- The computed structure of the jet is in good accord with
that observed in experiments. As the fluid leaves the nozzle,
the pressure mismatch generates a rapid expansion and a
down-running oblique shock wave. This shock interacts with
the expansion waves returning from the flow axis to form a
- Details of the experiments can be found in:
A study of free jet impingement, Part 1:
Mean properties of free and expanding jets
Donaldson C and Snedeker R S
Journal of Fluid Mechanics, Vol. 45, pp281-319, 1971.