Linear system setup and solution

Linear system setup and solution Подпись: U Подпись: и Подпись: Ux Uy Uz Подпись: cosa cose I с Г Ur I sine > , Cl = — = < йу > (6.38) sina cose L Uz

The subsequent numerical implementation of equations (6.37) will be done in terms of the following vari­ables normalized with VL, denoted by the overbar (). Note that U is then dimensionless, while Г and CC have units of length and 1/length, respectively.

Подпись: A. Подпись: Г, Linear system setup and solution Linear system setup and solution Подпись: (6.39)

The linearized flow tangency conditions (6.37) constitute an N x N linear system for the Г. normalized vortex strengths when the U, C, Si terms are placed on the righthand side.

Подпись: (6.40)A.j = Y?(ri) ‘ no.

The Aerodynamic Influence Coefficient matrix A., and the righthand side vectors in braces are functions of the vortex lattice geometry only, and hence are known a priori.

Multiplying (6.39) through by A-1 using LU-factorization and back-substitution gives the solution vector Г. as a sum of known 6+Ni independent vectors, whose coefficients (arbitrary at this point) are the operating

Linear system setup and solution Linear system setup and solution Подпись: (6.41)
Linear system setup and solution

parameters Ux, Uy … SN[. When these parameters are specified, Гi is determined by summing all 6 + N vectors.