EQP ROM workflow for unsteady NS

[dreamer2368]

ROMHandler block ordering

Previously, the blocks in the ROM system matrix are ordered by domain, i.e. for m-th subdomain and v-th variable, the block index is v + m * num_var.

Now block indexing supports two modes, specified by enum class ROMOrderBy:

• ROMOrderBy::DOMAIN: v + m * num_var
• ROMOrderBy::VARIABLE: m + v * numSub

This helps manipulating ROM matrix/vectors in the same way of FOM. Two auxiliary functions are also provided:

• ROMHandlerBase:: GetBlockIndex: from a domain and variable to block index
• ROMHandlerBase::GetDomainAndVariableIndex: from a block index to domain and variable

ROMHandler::SetRomMat

ROMHandler::SetRomMat now skips the LU factorization only when specified. Currently it does not skip anywhere.

mass matrix added in ROMLinearElement

ROMLinearElement now has the additional Matrix blocks for mass matrix. It can be created and saved only if needed.

Unsteady NS equation ROM solver

The ROM workflow for unsteady NS equation solver is implemented and verified:

• UnsteadyNSSolver::BuildCompROMLinElems
• UnsteadyNSSolver::AssembleROMMat
• UnsteadyNSSolver::SolveROM