Prandtl-Meyer Expansion
Centered expansion fan
The existing corner-flow view preserves the characteristic fan and upstream/downstream Mach angles.
Expansion fan geometry
Turning through the fan increases ν(M), accelerates the flow, and narrows the Mach angle.
M₂ 2.385
Expansion turn θ
10.00°
flow turn at the convex corner
ν₁
26.38°
upstream Prandtl-Meyer angle
ν₂
36.38°
downstream Prandtl-Meyer angle
μ₁
30.00°
upstream Mach angle
μ₂
24.79°
downstream Mach angle
Downstream Mach number
2.385
From M1 2.00
Expansion turn
10.00 deg
Centered fan
Upstream Prandtl-Meyer angle
26.380 deg
Mach angle 30.00 deg
Downstream Prandtl-Meyer angle
36.380 deg
Mach angle 24.79 deg
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