Dear All

I want to solve the following ordinary differential equation related to deflection of the cantilever beam.

dxx(w)=-P*x/E/I

BC1: w=0 at x=0

BC2: dw/dx=0 at x=0

I cannot impose the boundary condition BC2 correctly.

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TITLE 'Cantilever Beam' { the problem identification }

COORDINATES cartesian1 { coordinate system, 1D,2D,3D, etc }

VARIABLES

W

H

DEFINITIONS

L=1

P=200

E=70e9

I=1/12*0.03^4

ans_analytical=-(1/6)*P*x^3/(E*i)

EQUATIONS { PDE's, one for each variable }

H: H=dx(w)

W: dx(H)=-P*x/E/I

BOUNDARIES { The domain definition }

REGION 'domain' { For each material region }

START(0) { Walk the domain boundary }

point value (w)=0

point value (H)=0

LINE TO (L)

MONITORS { show progress }

PLOTS { save result displays }

elevation (w,ans_analytical) from (0) to (L) as "deflection"

END

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Why my script is not resulted in the correct solution?

How can I apply “Natural (Or load) Boundary condition” to solve my problem?

How can I impose boundary condition as DERIVATIVE in FlexPDE?

Thanks in advanced