Hi,

look at http://sfepy.org/doc-devel/examples/large_deformation/hyperelastic.html, there is the example with the user defined function for boundary conditions.

ebcs = { 'r' : ('Right', {'u.0' : 0.0, 'u.[1,2]' : 'rotate_yz'}), }

It defines the boundary condition applied to region 'Right', where u_x=0 and u_y, u_z are given by the user function 'rotate_yx':

def rotate_yz(ts, coor, **kwargs): from sfepy.linalg import rotation_matrix2d

 vec = coor[:,1:3] - centre

 angle = 10.0 * ts.step
 print 'angle:', angle

 mtx = rotation_matrix2d( angle )
 vec_rotated = nm.dot( vec, mtx )

 displacement = vec_rotated - vec

 return displacement.T.flat

SfePy calls this with two arguments: 'ts'= time step (not needed now) and 'coor'= coordinates of the region in which you define your own values.

Regards Vladimir

On 2015-12-09 14:43, Jacky Ko wrote:

This example clearly illustrated a simple application of sfepy with Navier Stokes problem.

http://sfepy.org/doc-devel/examples/navier_stokes/navier_stokes.html

The inlet/outlet definition:

region_1 = { 'name' : 'Inlet', 'select' : 'vertices by cinc0', # In 'kind' : 'facet', } region_2 = { 'name' : 'Outlet', 'select' : 'vertices by cinc1', # Out 'kind' : 'facet', }

ebc_1 = { 'name' : 'Walls', 'region' : 'Walls', 'dofs' : {'u.all' : 0.0}, } ebc_2 = { 'name' : 'Inlet', 'region' : 'Inlet', 'dofs' : {'u.1' : 1.0, 'u.[0,2]' : 0.0}, }

This only allows the velocity inlet normal to y axis. If I have an inlet plane that is arbitrary, let say with normal fluid inlet velocity (ux,uy,uz), how should I define the inlet boundary condition?

Moreover, is there any documentation to help me understanding following functions? the syntax is quite different from the typical python one.

functions = { 'cinc0' : (lambda coors, domain=None: cinc(coors, 0),), 'cinc1' : (lambda coors, domain=None: cinc(coors, 1),), }

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