Grid independent study is important in FLUENT for a certain geometry to get right answer, but is it necessary to do another grid independent study if we want to change the geometry and keep the same B.C in use?
For instance, the grid independent study have done for a pipe with 5 cm inlet diameter and by using same B.C but with different pipe diameter, for example 2.5cm, in this case do we need to repeat the grid independent study for 2.5cm pipe or not?