Solid/Liquid Flue Gas Material Calculator

Detailed Description

This calculator estimates the available heat and heat losses for solid and liquid fuel combustion by analyzing flue gas composition, excess air, stoichiometry, and enthalpy of reactants and products. The algorithm accounts for sensible, latent, unburned carbon, and ash losses to determine the percentage of fuel energy available for useful work.

The calculation follows a top-down approach:

1. Available Heat - Calculate percentage of fuel energy available after all losses
2. Input Heat - Sum sensible heat of fuel, combustion air, heating value, and moisture heat
3. Flue Gas Heat Loss - Calculate sensible and latent heat in exhaust products
4. Other Losses - Account for moisture, unburned carbon, and ash losses
5. Flue Gas Components - Determine mass of each combustion product
6. Stoichiometric Air - Calculate theoretical air requirements from fuel composition
7. Fuel Composition Normalization - Convert fuel analysis percentages to fractions

Each section presents formulas with complete symbol tables and engineering context for practical application in combustion system analysis, energy auditing, and process optimization.

Flue Gas Heat Loss Calculation

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Algorithm for calculating total heat loss and available heat for solid/liquid flue gas materials.

This section documents the complete algorithm for determining available heat from solid and liquid fuels. The calculation includes normalization of fuel composition, enthalpy calculations for fuel and air inputs, stoichiometric analysis, flue gas component analysis, and all major loss mechanisms.

Available Heat Calculation

Final available heat percentage after all losses.

Available heat is the fraction of input fuel energy remaining for useful work after accounting for sensible heat in flue gas, ash losses, and unburned carbon losses.

\begin{equation}\label{eq:slfgm-available-heat} Q_{avail} = \frac{h_{in} - h_{fg} - h_{ash} - h_{carbon}}{HV_{fuel}}\end{equation}

Symbols

\(Q_{avail}\)	Available heat fraction \([\unit{ \unitless}]\)
\(h_{in}\)	Total input heat \([\unit{ \btu\per\pound}]\)
\(h_{fg}\)	Total sensible heat in flue gas \([\unit{ \btu\per\pound}]\)
\(h_{ash}\)	Heat loss due to ash \([\unit{ \btu\per\pound}]\)
\(h_{carbon}\)	Heat loss due to unburned carbon \([\unit{ \btu\per\pound}]\)
\(HV_{fuel}\)	Heating value of fuel \([\unit{ \btu\per\pound}]\)

Input Heat

Total heat input from fuel, combustion air, and moisture.

Input heat includes the heating value of the fuel plus sensible heat contributions from elevated fuel temperature, preheated combustion air, and fuel moisture.

\begin{equation}\label{eq:slfgm-h-in} h_{in} = h_{fuel} + h_{combustion,air} + HV_{fuel} + h_{moisture}\end{equation}

Symbols

\(h_{in}\)	Total input heat \([\unit{ \btu\per\pound}]\)
\(h_{fuel}\)	Sensible heat in fuel \([\unit{ \btu\per\pound}]\)
\(h_{combustion,air}\)	Sensible heat in combustion air \([\unit{ \btu\per\pound}]\)
\(HV_{fuel}\)	Heating value of fuel \([\unit{ \btu\per\pound}]\)
\(h_{moisture}\)	Heat required for fuel moisture \([\unit{ \btu\per\pound}]\)

Sensible Heat of Flue Gas Components

Calculate heat content of each flue gas constituent.

For each component in the flue gas, calculate the sensible heat based on temperature rise and mass flow. Water vapor requires special treatment for latent heat of condensation.

\begin{equation}\label{eq:slfgm-h-sensible-co2} h_{CO_2} = m_{CO_2} \cdot \frac{Cp_{CO_2}}{MW_{CO_2}} \cdot (T_{fg} - T_{ref})\end{equation}

\begin{equation}\label{eq:slfgm-h-sensible-h2o} h_{H_2O} = m_{H_2O,fuel} \cdot (h_{sat} + \frac{Cp_{H_2O}}{MW_{H_2O}} \cdot (T_{fg} - T_{ref})) + m_{H_2O,air} \cdot (\frac{Cp_{H_2O}}{MW_{H_2O}} \cdot (T_{fg} - T_{ref}))\end{equation}

\begin{equation}\label{eq:slfgm-h-sensible-so2} h_{SO_2} = m_{SO_2} \cdot \frac{Cp_{SO_2}}{MW_{SO_2}} \cdot (T_{fg} - T_{ref})\end{equation}

\begin{equation}\label{eq:slfgm-h-sensible-o2} h_{O_2} = m_{O_2} \cdot \frac{Cp_{O_2}}{MW_{O_2}} \cdot (T_{fg} - T_{ref})\end{equation}

\begin{equation}\label{eq:slfgm-h-sensible-n2} h_{N_2} = m_{N_2} \cdot \frac{Cp_{N_2}}{MW_{N_2}} \cdot (T_{fg} - T_{ref})\end{equation}

\begin{equation}\label{eq:slfgm-h-fg} h_{fg} = h_{H_2O} + h_{CO_2} + h_{N_2} + h_{O_2} + h_{SO_2}\end{equation}

Symbols

\(h_{i}\)	Sensible heat of constituent i \([\unit{ \btu\per\pound}]\)
\(m_{i}\)	Mass of constituent i \([\unit{ \pound\per\poundFuel}]\)
\(Cp_{i}\)	Specific heat of constituent i - see Gas Constants \([\unit{ \btu\per\pound\degreeFahrenheit}]\)
\(MW_{i}\)	Molecular weight of constituent i - see Gas Constants \([\unit{ \pound\per\lbmol}]\)
\(T_{fg}\)	Flue gas temperature \([\unit{ \degreeFahrenheit}]\)
\(T_{ref}\)	Reference temperature (ambient) \([\unit{ \degreeFahrenheit}]\)
\(h_{sat}\)	Enthalpy of saturated steam \([\unit{ \btu\per\pound}]\)
\(m_{H_2O,fuel}\)	Water from fuel moisture and combustion \([\unit{ \pound\per\poundFuel}]\)
\(m_{H_2O,air}\)	Water from combustion air moisture \([\unit{ \pound\per\poundFuel}]\)
\(h_{fg}\)	Total sensible heat in flue gas \([\unit{ \btu\per\pound}]\)

Enthalpy of Saturated Steam

Calculate enthalpy at saturation for latent heat effects.

The enthalpy of saturated steam is needed to account for latent heat of condensation in the water vapor component of the flue gas.

\begin{equation}\label{eq:slfgm-h-sat} h_{sat} = 1096.7 \cdot (p_{H_2O} \cdot 29.926)^{0.013}\end{equation}

Symbols

\(h_{sat}\)	Enthalpy of saturated steam \([\unit{ \btu\per\pound}]\)
\(p_{H_2O}\)	Partial pressure of water vapor \([\unit{ \unitless}]\)
\(1096.7\)	Empirical correlation coefficient \([\unit{ \btu\per\pound}]\)
\(29.926\)	Atmospheric pressure in inches of mercury \([\unit{ \inchMercury}]\)
\(0.013\)	Empirical correlation exponent \([\unit{ \unitless}]\)

Partial Pressure of Water Vapor

Calculate mole fraction of water vapor in flue gas.

The partial pressure of water vapor is needed to determine saturation conditions for latent heat calculations. It is calculated from the volumetric fractions of all constituents using specific gravity ratios.

\begin{equation}\label{eq:slfgm-pp-h2o} p_{H_2O} = \frac{m_{H_2O}/0.047636}{m_{CO_2}/0.116367 + m_{H_2O}/0.047636 + m_{N_2}/0.074077 + m_{O_2}/0.084611 + m_{SO_2}/0.169381}\end{equation}

Symbols

\(p_{H_2O}\)	Partial pressure (mole fraction) of water vapor \([\unit{ \unitless}]\)
\(m_{i}\)	Mass of constituent i \([\unit{ \pound\per\poundFuel}]\)
\(0.047636\)	H2O specific weight - see Gas Constants \([\unit{ \pound\per\cubicFoot}]\)
\(0.116367\)	CO2 specific weight - see Gas Constants \([\unit{ \pound\per\cubicFoot}]\)
\(0.074077\)	N2 specific weight - see Gas Constants \([\unit{ \pound\per\cubicFoot}]\)
\(0.084611\)	O2 specific weight - see Gas Constants \([\unit{ \pound\per\cubicFoot}]\)
\(0.169381\)	SO2 specific weight - see Gas Constants \([\unit{ \pound\per\cubicFoot}]\)

Other Losses

Account for moisture, unburned carbon, and ash losses.

Additional heat losses occur due to moisture evaporation, incomplete combustion leaving unburned carbon in ash, and sensible heat carried away by hot ash.

\begin{equation}\label{eq:slfgm-h-moisture} h_{moisture} = X_{moisture} \cdot (T_{fg} - T_{ref})\end{equation}

\begin{equation}\label{eq:slfgm-h-carbon} h_{carbon} = 14093.0 \cdot X_{unburned,carbon} \cdot (X_{ash}/x_{fuel})\end{equation}

\begin{equation}\label{eq:slfgm-h-ash} h_{ash} = (X_{ash}/x_{fuel}) \cdot 0.25 \cdot (1.8 \cdot T_{ash,discharge} + 32.0 - T_{ref})\end{equation}

Symbols

\(h_{moisture}\)	Heat loss due to moisture evaporation \([\unit{ \btu\per\pound}]\)
\(h_{carbon}\)	Heat loss due to unburned carbon \([\unit{ \btu\per\pound}]\)
\(h_{ash}\)	Heat loss due to ash sensible heat \([\unit{ \btu\per\pound}]\)
\(X_{moisture}\)	Moisture percent in fuel \([\unit{ \percent}]\)
\(X_{unburned,carbon}\)	Unburned carbon in ash \([\unit{ \percent}]\)
\(X_{ash}\)	Ash percent in fuel \([\unit{ \percent}]\)
\(x_{fuel}\)	Dry fuel fraction \([\unit{ \unitless}]\)
\(T_{fg}\)	Flue gas temperature \([\unit{ \degreeFahrenheit}]\)
\(T_{ref}\)	Reference temperature (ambient) \([\unit{ \degreeFahrenheit}]\)
\(T_{ash,discharge}\)	Ash discharge temperature \([\unit{ \degreeFahrenheit}]\)
\(14093.0\)	Heating value of carbon \([\unit{ \btu\per\pound}]\)
\(0.25\)	Specific heat of ash \([\unit{ \btu\per\pound\degreeFahrenheit}]\)
\(1.8\)	Fahrenheit to Celsius conversion factor \([\unit{ \unitless}]\)
\(32.0\)	Fahrenheit to Celsius offset \([\unit{ \degreeFahrenheit}]\)

Flue Gas Components and Heating Value

Calculate mass of each flue gas component and fuel heating value.

The mass of each combustion product is calculated from fuel composition and stoichiometry. The heating value is the sum of elemental contributions from carbon, hydrogen, and sulfur. See Gas Constants for stoichiometric constants.

\begin{equation}\label{eq:slfgm-m-co2} m_{CO_2} = x_C \cdot k_{C\to CO_2}\end{equation}

\begin{equation}\label{eq:slfgm-m-h2o} m_{H_2O} = x_H \cdot k_{H\to H_2O} + x_{moisture} + (M_{comb,air} \cdot M_{air,moisture}/100)\end{equation}

\begin{equation}\label{eq:slfgm-m-so2} m_{SO_2} = x_S \cdot k_{S\to SO_2}\end{equation}

\begin{equation}\label{eq:slfgm-m-o2} m_{O_2} = O2_{s,air} \cdot EA\end{equation}

\begin{equation}\label{eq:slfgm-m-n2} m_{N_2} = N2_{s,air} \cdot (1 + EA)\end{equation}

\begin{equation}\label{eq:slfgm-hv} HV_{fuel} = x_C \cdot k_{HV,C} + x_H \cdot k_{HV,H} + x_S \cdot k_{HV,S}\end{equation}

Symbols

\(m_{i}\)	Mass of constituent i per unit fuel \([\unit{ \pound\per\poundFuel}]\)
\(x_C\)	Carbon mass fraction in fuel \([\unit{ \unitless}]\)
\(x_H\)	Hydrogen mass fraction in fuel \([\unit{ \unitless}]\)
\(x_S\)	Sulfur mass fraction in fuel \([\unit{ \unitless}]\)
\(x_{moisture}\)	Moisture mass fraction in fuel \([\unit{ \unitless}]\)
\(k_{C\to CO_2}\)	Carbon to CO2 stoichiometric ratio - see Gas Constants \([\unit{ \pound\per\pound}]\)
\(k_{H\to H_2O}\)	Hydrogen to H2O stoichiometric ratio - see Gas Constants \([\unit{ \pound\per\pound}]\)
\(k_{S\to SO_2}\)	Sulfur to SO2 stoichiometric ratio - see Gas Constants \([\unit{ \pound\per\pound}]\)
\(M_{comb,air}\)	Total combustion air \([\unit{ \pound\per\poundFuel}]\)
\(M_{air,moisture}\)	Moisture percent in combustion air \([\unit{ \percent}]\)
\(O2_{s,air}\)	Stoichiometric O2 required \([\unit{ \pound\per\poundFuel}]\)
\(N2_{s,air}\)	Stoichiometric N2 from air \([\unit{ \pound\per\poundFuel}]\)
\(EA\)	Excess air fraction \([\unit{ \unitless}]\)
\(HV_{fuel}\)	Heating value of fuel \([\unit{ \btu\per\pound}]\)
\(k_{HV,C}\)	Heating value of carbon \([\unit{ \btu\per\pound}]\)
\(k_{HV,H}\)	Heating value of hydrogen \([\unit{ \btu\per\pound}]\)
\(k_{HV,S}\)	Heating value of sulfur \([\unit{ \btu\per\pound}]\)
\(100\)	Percentage conversion factor \([\unit{ \unitless}]\)

Stoichiometric Air and Combustion Calculations

Calculate theoretical air requirements from fuel composition.

Stoichiometric air is the theoretical minimum air required for complete combustion. The calculation accounts for oxygen requirements of carbon, hydrogen, and sulfur, minus any oxygen present in the fuel. See Gas Constants for stoichiometric ratios.

\begin{equation}\label{eq:slfgm-stoich-air} O2_{s,air} = x_C \cdot k_{C\to O_2} + x_H \cdot k_{H\to O_2} + x_S \cdot k_{S\to O_2} - x_{O_2}\end{equation}

\begin{equation}\label{eq:slfgm-n2s-air} N2_{s,air} = O2_{s,air} \cdot k_{N_2/O_2}\end{equation}

\begin{equation}\label{eq:slfgm-ms-air} M_{s,air} = O2_{s,air} + N2_{s,air}\end{equation}

\begin{equation}\label{eq:slfgm-m-comb-air} M_{comb,air} = M_{s,air} \cdot (1 + EA)\end{equation}

Symbols

\(O2_{s,air}\)	Stoichiometric O2 required \([\unit{ \pound\per\poundFuel}]\)
\(N2_{s,air}\)	Stoichiometric N2 from air \([\unit{ \pound\per\poundFuel}]\)
\(M_{s,air}\)	Stoichiometric air \([\unit{ \pound\per\poundFuel}]\)
\(M_{comb,air}\)	Total combustion air \([\unit{ \pound\per\poundFuel}]\)
\(x_C\)	Carbon mass fraction in fuel \([\unit{ \unitless}]\)
\(x_H\)	Hydrogen mass fraction in fuel \([\unit{ \unitless}]\)
\(x_S\)	Sulfur mass fraction in fuel \([\unit{ \unitless}]\)
\(x_{O_2}\)	Oxygen mass fraction in fuel \([\unit{ \unitless}]\)
\(k_{C\to O_2}\)	Carbon to O2 stoichiometric ratio - see Gas Constants \([\unit{ \pound\per\pound}]\)
\(k_{H\to O_2}\)	Hydrogen to O2 stoichiometric ratio - see Gas Constants \([\unit{ \pound\per\pound}]\)
\(k_{S\to O_2}\)	Sulfur to O2 stoichiometric ratio - see Gas Constants \([\unit{ \pound\per\pound}]\)
\(k_{N_2/O_2}\)	N2 to O2 ratio in air - see Gas Constants \([\unit{ \pound\per\pound}]\)
\(EA\)	Excess air fraction \([\unit{ \unitless}]\)

Fuel and Combustion Air Enthalpy

Calculate sensible enthalpy of fuel and combustion air inputs.

When fuel or combustion air enters at temperatures above ambient, they contribute additional sensible heat to the system. The specific heat of combustion air varies with temperature.

\begin{equation}\label{eq:slfgm-h-fuel} h_{fuel} = C_{pfuel} \cdot (1 - x_{moisture}) \cdot (T_{fuel} - T_{amb})\end{equation}

\begin{equation}\label{eq:slfgm-cp-comb-air} C_{p,air} = a + b \cdot T_{comb}\end{equation}

\begin{equation}\label{eq:slfgm-h-comb-air} h_{comb,air} = M_{comb,air} \cdot C_{p,air} \cdot (T_{comb} - T_{amb}) / \rho_{air}\end{equation}

Symbols

\(h_{fuel}\)	Sensible enthalpy of fuel \([\unit{ \btu\per\pound}]\)
\(C_{pfuel}\)	Specific heat of fuel \([\unit{ \btu\per\pound\degreeFahrenheit}]\)
\(x_{moisture}\)	Moisture fraction in fuel \([\unit{ \unitless}]\)
\(T_{fuel}\)	Fuel temperature \([\unit{ \degreeFahrenheit}]\)
\(T_{amb}\)	Ambient air temperature \([\unit{ \degreeFahrenheit}]\)
\(C_{p,air}\)	Specific heat of combustion air \([\unit{ \btu\per\pound\degreeFahrenheit}]\)
\(a\)	Linear coefficient for air specific heat \([\unit{ \btu\per\pound\degreeFahrenheit}]\)
\(b\)	Temperature coefficient for air specific heat \([\unit{ \btu\per\pound\degreeFahrenheit\squared}]\)
\(T_{comb}\)	Combustion air temperature \([\unit{ \degreeFahrenheit}]\)
\(h_{comb,air}\)	Sensible enthalpy of combustion air \([\unit{ \btu\per\pound}]\)
\(M_{comb,air}\)	Mass of combustion air \([\unit{ \pound\per\poundFuel}]\)
\(\rho_{air}\)	Density of air \([\unit{ \pound\per\cubicFoot}]\)

Normalize Fuel Composition

Convert fuel analysis percentages to mass fractions.

Fuel composition is typically provided as percentages that may not sum to exactly 100%. Normalization ensures mass fractions sum to unity for stoichiometric calculations.

\begin{equation}\label{eq:slfgm-norm-fuel} x_i = \frac{X_i}{\sum_j X_j}\end{equation}

Symbols

\(x_i\)	Normalized mass fraction of constituent i \([\unit{ \unitless}]\)
\(X_i\)	Percent of constituent i in fuel \([\unit{ \percent}]\)

Excess Air Calculation

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Iterative method to estimate excess air from measured flue gas oxygen.

Given the measured O2 percentage in the flue gas and fuel composition, this algorithm iteratively estimates the fraction of excess air supplied to the combustion process. The calculation uses stoichiometric relationships and mass balance.

The implementation uses the shared process_heat::calculateExcessAir function from the Process Heat Utilities namespace as the initial estimate, then iteratively refines it based on the fuel composition and measured flue gas properties.

Iterative Procedure

1. Initial Estimate: Uses process_heat::calculateExcessAir to get a starting excess air value based on measured flue gas O2. See Excess Air from Flue Gas O2 for the formula.
2. Iterative Refinement: Calculates expected O2 using solid_liquid_flue_gas_material::calculateFlueGasO2 and adjusts excess air until convergence (error < 2%).
3. Convergence: Iteration continues until the calculated O2 matches the measured O2 within tolerance.

Symbols

\(EA\)	Excess air fraction \([\unit{ \unitless}]\)
\(O_2\)	Measured flue gas oxygen percentage \([\unit{ \percent}]\)

See also

process_heat::calculateExcessAir for the initial excess air estimate formula

solid_liquid_flue_gas_material::calculateFlueGasO2 for O2 calculation during iteration

Flue Gas O2 Calculation

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Compute expected oxygen content in flue gas for a given excess air level.

Given the excess air fraction and fuel composition, this algorithm calculates the expected O2 percentage in the flue gas using stoichiometric and mass balance relationships.

O2 Percentage

The O2 content is calculated from the mass of excess oxygen divided by the total flue gas mass, converted to volumetric percentage.

Symbols

\(O_2\)	Flue gas oxygen percentage \([\unit{ \percent}]\)
\(EA\)	Excess air fraction \([\unit{ \unitless}]\)

Heating Value Calculation

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Calculate higher heating value of solid or liquid fuel.

The higher heating value (HHV) is calculated as a weighted sum of elemental contributions from carbon, hydrogen, and sulfur in the fuel. The weights must be normalized fractions.

Normalization

First, normalize the fuel composition fractions:

\begin{equation}\label{eq:slfgm-norm-fuel-2} x_i = \frac{X_i}{\sum_j X_j}\end{equation}

Weighted Heating Value

Calculate heating value as weighted sum:

\begin{equation}\label{eq:slfgm-hv-calc} HV_{fuel} = x_C \cdot k_{HV,C} + x_H \cdot k_{HV,H} + x_S \cdot k_{HV,S}\end{equation}

Symbols

\(HV_{fuel}\)	Heating value of fuel \([\unit{ \btu\per\pound}]\)
\(x_C\)	Normalized carbon fraction \([\unit{ \unitless}]\)
\(x_H\)	Normalized hydrogen fraction \([\unit{ \unitless}]\)
\(x_S\)	Normalized sulfur fraction \([\unit{ \unitless}]\)
\(X_i\)	Percent of constituent i in fuel \([\unit{ \percent}]\)
\(k_{HV,C}\)	Heating value constant for carbon \([\unit{ \btu\per\pound}]\)
\(k_{HV,H}\)	Heating value constant for hydrogen \([\unit{ \btu\per\pound}]\)
\(k_{HV,S}\)	Heating value constant for sulfur \([\unit{ \btu\per\pound}]\)

See also

Solid/Liquid Flue Gas Material Database

Gas Constants for molecular weights, specific heat formulas, and stoichiometric constants

Modules
	Total Solid/Liquid Flue Gas: Heat Loss
	Algorithm for calculating total heat loss and available heat for solid/liquid flue gas materials.
	Excess Air Calculation
	Iterative method to estimate excess air from measured flue gas oxygen.
	Flue Gas O2 Calculation
	Compute expected oxygen content in flue gas for a given excess air level.
	Heating Value Calculation
	Calculate higher heating value of solid or liquid fuel.

Files
file	solid_liquid_flue_gas_material.h

Namespaces
namespace	solid_liquid_flue_gas_material
	Contains functions for flue gas material calculations.

Functions
double	solid_liquid_flue_gas_material::totalHeatLoss (const double flue_gas_temperature, const double excess_air, const double combustion_air_temperature, const double fuel_temperature, const double moisture_in_air_combustion, const double ash_discharge_temperature, const double unburned_carbon_in_ash, const double carbon, const double hydrogen, const double sulphur, const double inert_ash, const double o2, const double moisture, const double nitrogen, const double ambient_air_temp_f=60)
	Calculates total heat loss for solid/liquid fuel flue gas.
double	solid_liquid_flue_gas_material::calculateExcessAirFromFlueGasO2 (double flue_gas_o2, double carbon, double hydrogen, double sulphur, double inert_ash, double o2, double moisture, double nitrogen, double moisture_in_air_combustion)
	Calculates excess air percentage given flue gas O2 levels using iterative algorithm.
double	solid_liquid_flue_gas_material::calculateFlueGasO2 (double excess_air, double carbon, double hydrogen, double sulphur, double inert_ash, double o2, double moisture, double nitrogen, double moisture_in_air_combustion)
	Calculates flue gas O2 fraction given excess air and fuel composition.
double	solid_liquid_flue_gas_material::calculateHeatingValueFuel (double carbon, double hydrogen, double sulphur, double inert_ash, double o2, double moisture, double nitrogen)
	Calculates the heating value of the fuel based on composition.
double	solid_liquid_flue_gas_material::calculateStoichiometricAir (double carbon, double hydrogen, double sulphur, double inert_ash, double o2, double moisture, double nitrogen)
	Calculates the stoichiometric air required for complete combustion of the given fuel composition.

Function Documentation

calculateExcessAirFromFlueGasO2()

double solid_liquid_flue_gas_material::calculateExcessAirFromFlueGasO2	(	double	flue_gas_o2,
		double	carbon,
		double	hydrogen,
		double	sulphur,
		double	inert_ash,
		double	o2,
		double	moisture,
		double	nitrogen,
		double	moisture_in_air_combustion
	)

Parameters

[in]	flue_gas_o2	O2 percentage in flue gas \([\unit{\percent}]\)
[in]	carbon	Percent carbon in fuel \([\unit{\percent}]\)
[in]	hydrogen	Percent hydrogen in fuel \([\unit{\percent}]\)
[in]	sulphur	Percent sulphur in fuel \([\unit{\percent}]\)
[in]	inert_ash	Percent inert ash in fuel \([\unit{\percent}]\)
[in]	o2	Percent oxygen in fuel \([\unit{\percent}]\)
[in]	moisture	Percent moisture in fuel \([\unit{\percent}]\)
[in]	nitrogen	Percent nitrogen in fuel \([\unit{\percent}]\)
[in]	moisture_in_air_combustion	Percent moisture in combustion air \([\unit{\percent}]\)

Returns

Calculated excess air percentage \([\unit{\percent}]\)

calculateFlueGasO2()

double solid_liquid_flue_gas_material::calculateFlueGasO2	(	double	excess_air,
		double	carbon,
		double	hydrogen,
		double	sulphur,
		double	inert_ash,
		double	o2,
		double	moisture,
		double	nitrogen,
		double	moisture_in_air_combustion
	)

Parameters

[in]	excess_air	Excess air as fraction (e.g. 0.09 for 9%) \([\unit{\unitless}]\)
[in]	carbon	Percent carbon in fuel \([\unit{\percent}]\)
[in]	hydrogen	Percent hydrogen in fuel \([\unit{\percent}]\)
[in]	sulphur	Percent sulphur in fuel \([\unit{\percent}]\)
[in]	inert_ash	Percent inert ash in fuel \([\unit{\percent}]\)
[in]	o2	Percent oxygen in fuel \([\unit{\percent}]\)
[in]	moisture	Percent moisture in fuel \([\unit{\percent}]\)
[in]	nitrogen	Percent nitrogen in fuel \([\unit{\percent}]\)
[in]	moisture_in_air_combustion	Percent moisture in combustion air \([\unit{\percent}]\)

Returns

Calculated O2 fraction in flue gas \([\unit{\unitless}]\)

calculateHeatingValueFuel()

double solid_liquid_flue_gas_material::calculateHeatingValueFuel	(	double	carbon,
		double	hydrogen,
		double	sulphur,
		double	inert_ash,
		double	o2,
		double	moisture,
		double	nitrogen
	)

Parameters

[in]	carbon	Percent carbon in fuel \([\unit{\percent}]\)
[in]	hydrogen	Percent hydrogen in fuel \([\unit{\percent}]\)
[in]	sulphur	Percent sulphur in fuel \([\unit{\percent}]\)
[in]	inert_ash	Percent inert ash in fuel \([\unit{\percent}]\)
[in]	o2	Percent oxygen in fuel \([\unit{\percent}]\)
[in]	moisture	Percent moisture in fuel \([\unit{\percent}]\)
[in]	nitrogen	Percent nitrogen in fuel \([\unit{\percent}]\)

Returns

Heating value of the fuel \([\unit{\btu\per\pound}]\)

calculateStoichiometricAir()

double solid_liquid_flue_gas_material::calculateStoichiometricAir	(	double	carbon,
		double	hydrogen,
		double	sulphur,
		double	inert_ash,
		double	o2,
		double	moisture,
		double	nitrogen
	)

Uses the fuel composition (percent by mass) to compute the theoretical air required for complete combustion.

Parameters

[in]	carbon	Percent carbon in fuel \([\unit{\percent}]\)
[in]	hydrogen	Percent hydrogen in fuel \([\unit{\percent}]\)
[in]	sulphur	Percent sulphur in fuel \([\unit{\percent}]\)
[in]	inert_ash	Percent inert ash in fuel \([\unit{\percent}]\)
[in]	o2	Percent oxygen in fuel \([\unit{\percent}]\)
[in]	moisture	Percent moisture in fuel \([\unit{\percent}]\)
[in]	nitrogen	Percent nitrogen in fuel \([\unit{\percent}]\)

Returns

Stoichiometric air required \([\unit{\pound\per\poundFuel}]\)

totalHeatLoss()

double solid_liquid_flue_gas_material::totalHeatLoss	(	const double	flue_gas_temperature,
		const double	excess_air,
		const double	combustion_air_temperature,
		const double	fuel_temperature,
		const double	moisture_in_air_combustion,
		const double	ash_discharge_temperature,
		const double	unburned_carbon_in_ash,
		const double	carbon,
		const double	hydrogen,
		const double	sulphur,
		const double	inert_ash,
		const double	o2,
		const double	moisture,
		const double	nitrogen,
		const double	ambient_air_temp_f = 60
	)

Parameters

[in]	flue_gas_temperature	Flue gas temperature \([\unit{\degreeFahrenheit}]\)
[in]	excess_air	Excess air as fraction (e.g. 0.09 for 9%) \([\unit{\unitless}]\)
[in]	combustion_air_temperature	Combustion air temperature \([\unit{\degreeFahrenheit}]\)
[in]	fuel_temperature	Fuel temperature \([\unit{\degreeFahrenheit}]\)
[in]	moisture_in_air_combustion	Moisture in air combustion \([\unit{\percent}]\)
[in]	ash_discharge_temperature	Ash discharge temperature \([\unit{\degreeFahrenheit}]\)
[in]	unburned_carbon_in_ash	Unburned carbon in ash as fraction \([\unit{\unitless}]\)
[in]	carbon	Percent carbon in fuel \([\unit{\percent}]\)
[in]	hydrogen	Percent hydrogen in fuel \([\unit{\percent}]\)
[in]	sulphur	Percent sulphur in fuel \([\unit{\percent}]\)
[in]	inert_ash	Percent inert ash in fuel \([\unit{\percent}]\)
[in]	o2	Percent oxygen in fuel \([\unit{\percent}]\)
[in]	moisture	Percent moisture in fuel \([\unit{\percent}]\)
[in]	nitrogen	Percent nitrogen in fuel \([\unit{\percent}]\)
[in]	ambient_air_temp_f	Ambient air temperature \([\unit{\degreeFahrenheit}]\) (default: 60)

Returns

Total heat loss \([\unit{\btu\per\hour}]\)