SteamGen Expert (SGE) is a Windows-based program that performs the mass and energy balance calculations for fossil fueled combustion systems. It has a graphic user interface (GUI) allowing a user to set up a flow sheet that contains multiple modules connected by inlet and outlet streams. The current version of SteamGen Expert has ten categories of modules, namely, Furnace, Reactor, Heat Exchanger, Air Preheater, Air Pollution Control, Fuel Prep, Flow, Process, Pump, and Other. A stream can contain solid, liquid, and/or gas phases. The thermodynamic properties of commonly used gaseous, liquid and solid species are built in the program. After the input streams and the operating parameters of the modules in the system are specified, SGE will calculate the pressures, temperatures, and compositions of the outlet streams of all modules on the flow sheet. Energy balance will also be performed for each module in the system. If the heat input to a module is specified, the temperature of the outlet streams will be calculated. If the temperature of the outlet streams of a module is given, the heat input to the module will be calculated.


  • The program performs mass balance for C, H, O, N and S elements as well as ash in typical fossil fuel related applications.
  • There are about 30 available gas species for a user to choose from with built-in chemical and physical properties. Solid and liquid fuels can be specified based on their elemental composition and heating values.
  • Combustion reactions in a furnace can be modeled using the Furnace module.
  • Gas phase equilibrium calculation can be performed using the Equilibirum Reactor module.
  • Physical process such as moisture vaporization can be modeled using the Pulverizer module.
  • Streams can be split or combined using the Slitter and Union modules.
  • Liquid and solid phases in a stream can be separated using the Phase Separator module.
  • Pressure change in a stream and energy addition/removal to a stream can be modeled using the Fan module.
  • Valence based equivalence ratio and particle/droplet loading for each stream, if applicable, can be calculated and displayed. Actual stoichiometric ratio can be obtained using a tool in the program.
  • The program contains a tool to solve the required flow rate for a fuel or oxidizer stream based on the desired oxygen concentration in a product stream.
  • The program performs the conversion between particle burnout and loss on ignition (LOI) for solid fuel combustion and the conversion of NOx emissions between ppm, lb/MMBtu, and other units.
  • A user can choose his or her preferred unit of physical quantity for data input and output.
  • Detailed calculation data can be exported to a Microsoft Excel spreadsheet.
  • The current version has a context-sensitive help system.


Furnace Expert program is a handy tool for an engineer to perform basic mass and energy balances for a variety of combustion systems ranging from a simple combustion test facility to a utility power plant. It can be used to arrange the fuel and oxidizer distributions inside a combustor or gasifier to achieve desired stoichiometries. Since the code has the built-in properties for commonly used species, it can also be used to calculate the properties of a stream such as heat capacity, enthalpy, heating values, sensible heat, density, and molecular weight. For Computational Fluid Dynamics (CFD) modelers, Furnace Expert can be used as a tool to calculate the inlet and outlet boundary conditions or to check the CFD simulation results.