Sensitivity of a Plug Flow Reactor to Model Parameters
Plots of temperature and molar flow rates versus reactor volume are shown for gas-phase reactions in a non-isothermal, plug flow reactor (PFR). Both reactions are first order and only is fed to the reactor. Use the sliders to vary the inlet molar flow rate, feed temperature, and seven model parameters (a maximum of 10%) to see how sensitive the temperature and molar flow rates are to values used in the reactor model (parametric sensitivity). Since parameters used in a reactor model are not always known accurately, doing a parametric sensitivity analysis could identify potential problems.
where is the rate of reaction (), is the rate constant (1/s), is activation energy (kJ/mol), is a pre-exponential factor (1/s), is the ideal gas constant (kJ/[mol K]), is reaction temperature (K), and are the concentrations of and (), the subscript refers to the inlet, , , and are the molar flow rates of , , and (mol/s), and is the total molar flow rate (mol/s).
Mole and energy balances are done around the reactor:
where is volume (), is the heat transfer coefficient times heat transfer area per volume (kJ/[m s K]), is the coolant temperature (K), is heat of reaction (kJ/mol), and , and are the heat capacities of , and (kJ/[mol K]).
The screencast video at  explains how to use this Demonstration.