RCAIDE.Library.Methods.Aerodynamics.Airfoil_Panel_Method.thwaites_method
thwaites_method#
- thwaites_method(npanel, ncases, ncpts, NU, L, RE_L, X_I, VE_I, DVE_I, tol, wrong_columns, THETA_0)[source]#
Computes the boundary layer characteristics in laminar flow pressure gradients
Source: Thwaites, Bryan. “Approximate calculation of the laminar boundary layer.” Aeronautical Quarterly 1.3 (1949): 245-280.
Assumptions: None
Inputs: npanel - number of points on surface [unitless] ncases - number of cases [unitless] ncpts - number of control points [unitless] batch_analysis - flag for batch analysis [boolean] THETA_0 - initial momentum thickness [m] L - normalized length of surface [unitless] RE_L - Reynolds number [unitless] X_I - x coordinate on surface of airfoil [unitless] VE_I - boundary layer velocity at transition location [m/s] DVE_I - initial derivative value of boundary layer velocity at transition location [m/s-m] tol - boundary layer error correction tolerance [unitless]
Outputs: RESULTS.
X_T - reshaped distance along airfoil surface [unitless] THETA_T - momentum thickness [m] DELTA_STAR_T - displacement thickness [m] H_T - shape factor [unitless] CF_T - friction coefficient [unitless] RE_THETA_T - Reynolds number as a function of momentum thickness [unitless] RE_X_T - Reynolds number as a function of distance [unitless] DELTA_T - boundary layer thickness [m]
Properties Used: N/A
- getH(lambda_val)[source]#
Computes the shape factor, H
Assumptions: None
Source: None
Inputs: lamdda_val - thwaites separation criteria [unitless]
Outputs: H - shape factor [unitless]
Properties Used: N/A
- getcf(lambda_val, Re_theta)[source]#
Computes the skin friction coefficient, cf
Assumptions: None
Source: None
Inputs: lambda_val - thwaites separation criteria [unitless] Re_theta - Reynolds Number as a function of momentum thickness [unitless]
Outputs: cf - skin friction coefficient [unitless]
Properties Used: N/A