Non constant boundary conditions - PDE modeler toolbox

I am trying to implement a boundary condition that depends on the temperature gradient at a specific edge of a 2D cylindrical axisymmetric problem. To do so, I am defining a function that depends on @(location, state). The code is the following:

flux = @(location,state) ...

-k_evap(0,state).state.ur.*(location.y >= 0 & location.y <= l_evap & location.y >= (l_evap+l_adiab) & location.y <= (l_evap+l_adiab+l_cond)) + ...

-k_adiab(0,state).*state.ur.*(location.y > l_evap & location.y < (l_evap+l_adiab));

% Spatial BC

thermalBC(thermalModelHP_steady,'Edge',2, 'HeatFlux', 0); % Evaporator end plate - Na

thermalBC(thermalModelHP_steady,'Edge',1, 'HeatFlux', flux,...

'Vectorized', 'on'); % Na-wick interface

thermalBC(thermalModelHP_steady,'Edge',3, 'HeatFlux', 0); % Condenser end plate - Na

% thermalBC(thermalModelHP_steady,'Edge',4, 'HeatFlux', 0); % Symmetry (dudx = 0): not needed because the problem is specified as axisymmetric

However, I get the following error:

Dot indexing is not supported for variables of this type.

Someone knows why I get this error?

I defined other (material) properties that are temperature dependent in a similar way and their definition give me no problem... However this one does.

Thanks in advance!

Answer 1

[Rangesh]

Hi Pierluigi,

I see you are encountering an issue related to "Dot indexing."

“Dot indexing” involves accessing data fields within a data type known as a “struct”. The “struct” array organizes related data using fields as data containers. Accessing a field is typically done using the dot notation in the form of “structName.fieldName”.

The error you are encountering usually indicates that the variable is not a struct, thus preventing access. It would be better to check the data type of the variable that is causing the error.

For more details, you can refer to the following documentation:

• struct: https://www.mathworks.com/help/matlab/ref/struct.html

If this doesn't resolve the error, it would be beneficial to provide the complete code to better understand where the problem lies.

I hope this helps to address your concern.