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Rayleigh Flow Calculator

Compressible Flow in a Frictionless Constant Area Duct with Heat Transfer

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Select calculation: Mach number, M:
Specific heat ratio, k:
www.​LMNOeng.com Stag pressure ratio, Po/Po*: 
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Equations (Fox and McDonald, 1978; Munson et al., 1998; Shames, 1992)

Po/Po* = (k+1)/(kM2 + 1){[ (2/(k+1)][1 + (k-1)M2 / 2]}k/(k-1)

To/To* = 2 M2 (k+1)[1 + (k-1)M2 / 2] / (1 + kM2)2

P/P* = (k+1) / (1 + kM2)

T/T* = [(k+1)M / (1 + kM2)]2

V/V* = (k+1)M2 / (1 + kM2)


Variables (* indicates sonic conditions)

k = Specific heat at constant pressure divided by specific heat at constant volume, Cp / Cv
M = Mach number
Po/Po* = Stagnation pressure divided by stagnation pressure at sonic conditions
To/To* = Stagnation temperature divided by stagnation temperature at sonic conditions
P/P* = Static pressure divided by static pressure at sonic conditions
T/T* = Static temperature divided by static temperature at sonic conditions
V/V* = Velocity divided by sonic velocity


References

Fox, R. W. and A. T. McDonald. 1978. Introduction to Fluid Mechanics. John Wiley and Sons, Inc. 2ed.

Munson, B.R., D. F. Young, and T. H. Okiishi. 1998. Fundamentals of Fluid Mechanics. John Wiley and Sons, Inc. 3ed.

Shames, I. H. 1992. Mechanics of Fluids. McGraw-Hill, Inc. 3ed.

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