When specifying line and surface function-object-based visualisation, use the optional 'clearObjects' flag to indicate that source objects should be removed/cleared after use.
Test case: cavity.tgz
Syntax:
surfaces
{
cuttingPlane1
{
type functionObject;
functionObject cuttingPlane;
clearObjects yes; // new option
...Note: only files that have been used will be removed, e.g. if a function object has created multiple surface files, unused files will remain at the end of the run - in the attached case the p surface remains...