Element Deletion

Hi,

I would like to know or if it is possible for element deletion based on a criterion. For example, I have 3D cube geometry and a value “u2” which will be computed at each time step. If the value of “u2 < 250” then I want to delete that element.

Also, I want to define the another value “u1” on the new boundary to be 1 which was also 1 on the initial boundary surfaces.

If its possible, please reply so that I can further share my exact problem which I am trying to analyze.

Thanks in advance.