FlowBal is a spreadsheet-based heat and material balance program that uses the FREED database. FlowBal calculates heat and material balances for steady state process flow. Process devices include reactors, mixers, splitters, and heat exchangers, with both bypass and recycle flow. Material balance equations are automatiocally written around each device, and Excel’s Solver tool calculates up to 100 unknown stream variables.
The user can specify a variety of system constraints, including the equilibrium position for part or all of the reactions. FlowBal simulates a feedback controller by setting an output target. FlowBal then searches for an input variable that satisfies the target. Unsteady-state or time-variable flow systems can be simulated by dividing a steady-state process into a discreet number of steps and using FlowBal to solve each step.