Wall Shear Stress - Flat Plate
This module contains functions to estimate the wall shear stress and related coefficients for a incompressible/compressible, laminar/turbulent flat plate.
The two most important functions are: wss_ic, wss_c, as they are
wrapper functions that allows to estimates all parameters with a single call.
- pygasflow.atd.avf.wall_shear_stress_fp.wss_ic(rho, u, Re, laminar=True, to_dict=False)[source]
Compute the wall shear stress and friction coefficients for an incompressible flat plate.
- Parameters
- rhofloat or array_like
Free stream density.
- ufloat or array_like
Free stream velocity.
- Refloat or array_like
Free stream Reynolds number computed at some location.
- laminarbool, optional
Default to True, which computes the results for the laminar case. Set
laminar=Falseto compute turbulent results.- to_dictbool, optional
If False, the function returns a list of results. If True, it returns a dictionary in which the keys are listed in the Returns section. Default to False (return a list of results).
- Returns
- tau_wfloat or array_like
Wall shear stress, tau_w.
- cffloat or array_like
Skin friction coefficient.
- CDffloat or array_like
Friction drag coefficient.
See also
- pygasflow.atd.avf.wall_shear_stress_fp.wss_c(rhoinf, uinf, Reinf, Ts_Tinf, laminar=True, omega=0.65, to_dict=False)[source]
Compute the wall shear stress and friction coefficients for a compressible flat plate.
- Parameters
- rhoinffloat or array_like
Free stream density.
- uinffloat or array_like
Free stream velocity.
- Reinffloat or array_like
Free stream Reynolds number computed at some location.
- Ts_Tinffloat or array_like
Temperature ratio T* / Tinf between the reference temperature T* and the free stream temperature Tinf.
- laminarbool, optional
Default to True, which computes the results for the laminar case. Set
laminar=Falseto compute turbulent results.- omegafloat, optional
Exponent of the viscosity power law. Default to 0.65, corresponding to T > 400K. Set
omega=1otherwise.- to_dictbool, optional
If False, the function returns a list of results. If True, it returns a dictionary in which the keys are listed in the Returns section. Default to False (return a list of results).
- Returns
- tau_wfloat or array_like
Wall shear stress, tau_w.
- cffloat or array_like
Skin friction coefficient.
- CDffloat or array_like
Friction drag coefficient.
See also
- pygasflow.atd.avf.wall_shear_stress_fp.skin_friction(tau_w, q)[source]
Compute the skin friction coefficient, cf.
- Parameters
- tau_wfloat or array_like
Wall Shear Stress.
- qfloat or array_like
Dynamic pressure.
- Returns
- outfloat or array_like
Laminar Incompressible
- pygasflow.atd.avf.wall_shear_stress_fp.wss_lam_ic(rho, u, Re)[source]
Compute the wall shear stress for a laminar incompressible flat plate.
- Parameters
- rhofloat or array_like
Free stream density.
- ufloat or array_like
Free stream velocity.
- Refloat or array_like
Free stream Reynolds number computed at some location.
- Returns
- outfloat or array_like
See also
Laminar Compressible
- pygasflow.atd.avf.wall_shear_stress_fp.wss_lam_c(rhoinf, uinf, Reinf, Ts_Tinf, omega=0.65)[source]
Compute the wall shear stress for a laminar compressible flat plate.
- Parameters
- rhoinffloat or array_like
Free stream density.
- uinffloat or array_like
Free stream velocity.
- Reinffloat or array_like
Free stream Reynolds number computed at some location.
- Ts_Tinffloat or array_like
Temperature ratio T* / Tinf between the reference temperature T* and the free stream temperature Tinf.
- omegafloat, optional
Exponent of the viscosity power law. Default to 0.65, corresponding to T > 400K. Set
omega=1otherwise.
- Returns
- outfloat or array_like
See also
- pygasflow.atd.avf.wall_shear_stress_fp.friction_drag_lam_c(Re, Ts_Tinf, omega=0.65)[source]
Compute the friction drag coefficient, C_Df, for a laminar compressible flat plate.
- Parameters
- Refloat or array_like
Free stream Reynolds number computed with a reference length.
- Ts_Tinffloat or array_like
Temperature ratio T* / Tinf between the reference temperature T* and the free stream temperature Tinf.
- omegafloat, optional
Exponent of the viscosity power law. Default to 0.65, corresponding to T > 400K. Set
omega=1otherwise.
- Returns
- outfloat or array_like
Turbulent Incompressible
- pygasflow.atd.avf.wall_shear_stress_fp.wss_tur_ic(rho, u, Re)[source]
Compute the wall shear stress for a turbulent incompressible flat plate.
- Parameters
- rhofloat or array_like
Free stream density.
- ufloat or array_like
Free stream velocity.
- Refloat or array_like
Free stream Reynolds number computed at some location.
- Returns
- outfloat or array_like
See also
Turbulent Compressible
- pygasflow.atd.avf.wall_shear_stress_fp.wss_tur_c(rhoinf, uinf, Reinf, Ts_Tinf, omega=0.65)[source]
Compute the wall shear stress for a turbulent compressible flat plate.
- Parameters
- rhoinffloat or array_like
Free stream density.
- uinffloat or array_like
Free stream velocity.
- Reinffloat or array_like
Free stream Reynolds number computed at some location.
- Ts_Tinffloat or array_like
Temperature ratio T* / Tinf between the reference temperature T* and the free stream temperature Tinf.
- omegafloat, optional
Exponent of the viscosity power law. Default to 0.65, corresponding to T > 400K. Set
omega=1otherwise.
- Returns
- outfloat or array_like
See also
- pygasflow.atd.avf.wall_shear_stress_fp.friction_drag_tur_c(Re, Ts_Tinf, omega=0.65)[source]
Compute the friction drag coefficient, C_Df, for a turbulent compressible flat plate.
- Parameters
- Refloat or array_like
Free stream Reynolds number computed with a reference length.
- Ts_Tinffloat or array_like
Temperature ratio T* / Tinf between the reference temperature T* and the free stream temperature Tinf.
- omegafloat, optional
Exponent of the viscosity power law. Default to 0.65, corresponding to T > 400K. Set
omega=1otherwise.
- Returns
- outfloat or array_like