Bad velocity derivative in Radial Flow 1 elem example

[luchete80]

In 1 element radial Flow, one component of F derivative in one gauss point is null.

FIRST GAUSS POINT rg,sg -0.5773502691896258 -0.5773502691896258

UV [[ 0.04980974] [ 0.00435778] [ 0.09961947] [ 0.00871557] [ 0.09961947] [-0.00871557] [ 0.04980974] [-0.00435778]]

v [[ 0.08909343] [-0.00450025]]

dVxy [[-0.05 ] [ 0. ] [ 0.00625492] [ 0.07383136]]

for l in range(4): for m in range(16):
for n in range(2): temp[l,n]=temp[l,n]+BsigF[l,m,n]*UF[m] print("temp[l,n]",temp) F derivative temp[l,n] [[0. 0.] [0. 0.] [0. 0.] [0. 0.]]

But for this example: Vx=kcost Vy=ksint

Being t=atan(y/x)

Dvx/dx=-ksint

[luchete80]

Related to #83

[luchete80]

[luchete80]

B=(h1'x 0 h1'x... h1'y. 0 h1'y...) so, second component of dv/dxy is dvx/dy

[luchete80]

[luchete80]

Created example to compare derivatives

[luchete80]

This is not an error. Dvx/dy is null with 1 elem