Rayleigh Flow Calculator

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

Equations for Rayleigh Calculation (Fox and McDonald, 1978; Munson et al., 1998; Shames, 1992):

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

T_o/T_o^* = 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, C_p / C_v
M = Mach number
P_o/P_o^* = Stagnation pressure divided by stagnation pressure at sonic conditions
T_o/T_o^* = 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.

Please contact us for consulting or questions about compressible gas flow.

LMNO Engineering, Research, and Software, Ltd.
7860 Angel Ridge Rd. Athens, Ohio 45701 USA Phone: (740) 707-2614
LMNO@LMNOeng.com https://www.LMNOeng.com

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