Rayleigh Flow Calculator

One-dimensional compressible flow of an ideal gas in a frictionless constant area duct with heat transfer.


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Select calculation: Mach number, M:
Specific heat ratio, k:
Stag pressure ratio, Po/Po*: 
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Equations for Rayleigh Calculation (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 for Rayleigh Calculation (* 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

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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