public final class AeroMethods
extends java.lang.Object
Written by: Joseph A. Huwaldt
Modifier and Type | Method and Description |
---|---|
static double |
karmenTsien(double coef0,
double M)
Karman-Tsien compressibility correction.
|
static void |
main(java.lang.String[] args)
A simple method to test the methods in this class.
|
static double |
Mcr(double Cp0min,
double gam,
double tol)
Estimates the critical Mach number given the minimum
incompressible pressure coefficient.
|
static double |
prandtlGlauert(double coef0,
double M)
Prandtl-Glauert compressibility correction.
|
static double |
turbSkinFriction(double M1,
double twratio,
double R1)
Function that calculates the turbulent skin friction coefficient in a
boundary layer including the effects of compressibility, viscosity, and
heat transfer.
|
static double |
viscosityRatio(double tratio)
Calculates the viscosity ratio (mu/muref) as a function of the temperature
ratio (T/Tref).
|
public static double prandtlGlauert(double coef0, double M)
Prandtl-Glauert compressibility correction. A compressibility correction that relates incompressible flow over a given 2D profile to subsonic compressible flow over the same profile. It approximately corrects incompressible data for compressibility effects.
Generally, the Karman-Tsien correction is considered more accurate, but this method is provided for historical reasons.
coef0
- Any 2D coefficient (pressure, lift, drag, etc)
that is valid at M=0 (incompressible flow)
which you want to scale to a subsonic
compressible Mach number.M
- The subsonic Mach number you want to scale
the coef0 to.java.lang.IllegalArgumentException
- if the Mach number is not
subsonic.public static double karmenTsien(double coef0, double M)
coef0
- Any 2D coefficient (pressure, lift, drag, etc)
that is valid at M=0 (incompressible flow)
which you want to scale to a subsonic
compressible Mach number.M
- The subsonic Mach number you want to scale
the coef0 to.java.lang.IllegalArgumentException
- if the Mach number is not
subsonic.public static double Mcr(double Cp0min, double gam, double tol) throws jahuwaldt.tools.math.RootException
Cp0min
- The measured or calculated value of the
incompressible pressure coefficient at the
minimum pressure point.gam
- The specific heat ratio of the gas. For
air, the value is 1.4.tol
- Tolerance to use when calculating Mach
number.jahuwaldt.tools.math.RootException
- if there is a problem in the root
solver with converging on Mcr.public static double viscosityRatio(double tratio)
tratio
- The temperature ratio (T/Tref) at which the viscosity
ratio (mu/muref) is to be evaluated.public static double turbSkinFriction(double M1, double twratio, double R1)
M1
- The local Mach number just outside the boundary layer.twratio
- The local wall-temperature ratio (Tw/T1). T1 is the
local temperature just outside of the boundary layer,
Tw is the temperature at the wall.R1
- The local Reynolds number just outside of the boundary layer.public static void main(java.lang.String[] args)