[Nektar-users] Expansion Types and IncNavierStokesSolver

Dear All, I searched the web site of Nektar++ but I couldn't find any detailed information about the EXPANSION types (MODIFIED, GLL_LAGRANGE & GLL_LAGRANGE_SEM) used when using IncNavierStokesSolver. What are the differences between these Expansion types? Which one of these expansion types is the most suitable for problems like pipe flow or blood flow in vessels etc. ? Regards, Kamil