Tank (holdup vessel) simulation

N inlets -> 1 outlet (adiabatic mix at steady state; carries inventory in the dynamic/live engines — a level-control accumulator)

Governing equations

The exact equations the solver works for a tank (holdup vessel) — the same math shown in the app's "Theory" panel, not a black box.

$F$

molar flow [mol/s] — inlet(s) and outlet

$z$

mole fraction of component i; the outlet is the inlets blended by flow

$k$

index over the inlet streams

$N$

the vessel's molar inventory (dynamic engines only; no accumulation at steady state)

$N_{ss}$

the steady-state (design) inventory the level is normalized against

Parameters

optional pressure [Pa] outlet override (default = the minimum inlet pressure). A holdup vessel: steady-state passthrough/mix; its inventory (level) is dynamic in the live engine, where a feed-flow controller can hold its level via a level_transmitter.

Example flowsheets that use it