EP4636310A1

EP4636310A1 - A fuel identification and flame behavior monitoring system

Info

Publication number: EP4636310A1
Application number: EP25171412.7A
Authority: EP
Inventors: Ahmed Hasan
Original assignee: Carrier Corp
Current assignee: Carrier Corp
Priority date: 2024-04-18
Filing date: 2025-04-17
Publication date: 2025-10-22

Abstract

Described herein is a fuel identification and flame behavior monitoring system. The system comprises one or more sensors configured to monitor photons emitted from a flame emission during combustion of a fuel and correspondingly generate one or more spectrum signals associated with one or more radicals generated from the flame emission. A controller in communication with the one or more sensors is configured to determine a fuel composition of the fuel based on a variation in the one or more generated spectrum signals. The one or more generated spectrum signals vary based on an intensity ratio associated with the one or more radicals.

Description

This patent application claims the benefit of U.S. Provisional Patent Application No. 63/636,062, filed on April 18, 2024 , which is incorporated by reference herein in its entirety.
The invention relates to furnace systems in air conditioning systems.
According to a first aspect of the present invention there is provided a fuel identification and flame behavior monitoring system. The system comprises one or more sensors configured to monitor photons emitted from a flame emission during combustion of a fuel and correspondingly generate one or more spectrum signals associated with one or more radicals generated from the flame emission. A controller is in communication with the one or more sensors, the controller configured to determine a fuel composition of the fuel based on a variation in the one or more generated spectrum signals, where the one or more generated spectrum signals vary based on an intensity ratio associated with the one or more radicals.
Optionally, the controller is configured to determine an amount of air and an amount of fuel to be supplied for combustion in a gas furnace for combustion of the fuel therein based on the determined fuel composition.
Optionally, the one or more sensors comprise a light sensor operating in a range of 200-700nm for monitoring photons emitted from the flame emission.
Optionally, the one or more generated spectrum signals are chemiluminescence signals indicative of electromagnetic radiations occurring or the photons generated due to transitions of the one or more radicals emitted during the fuel combustion.
Optionally, at least a first radical of the one or more radicals is an OH* radical that generates the flame emission of a wavelength of 310nm, and a second radical of the one or more radicals is a CH* radical that generates the flame emission of a wavelength of 430nm.
Optionally, the controller is configured to measure the intensity ratio based on a ratio of the OH*/CH* radicals and correspondingly determine the fuel composition.
Optionally, upon detection of an increase in the flame emission associated with the OH* radical and/or the CH* radical, the controller is configured to detect an increase in a flame temperature and a corresponding variation in the one or more spectrum signals.
Optionally, upon detection of a decrease in the flame emission associated with the OH* radical and/or the CH* radical, the controller is configured to detect an increase in the amount of airflow available for the combustion and a corresponding variation in the one or more spectrum signals.
Optionally, an inducer associated with the gas furnace is operatively connected to the controller, wherein the controller is configured to actuate the inducer to control the airflow into the gas furnace for combustion, based on the determined fuel composition.
Optionally, a gas valve associated with the gas furnace is operatively connected to the controller, wherein the controller is configured to actuate the gas valve to control the amount of the fuel injected into the gas furnace based on the determined fuel composition.
According to a second aspect of the present invention there is provided a method for fuel identification and flame behavior monitoring. The method comprises monitoring, by one or more sensors, photons emitted from a flame emission during combustion of a fuel and correspondingly generating one or more spectrum signals associated with one or more radicals generated from the flame emission. The method comprises determining, by a controller, the fuel composition of a fuel based on a variation in the one or more generated spectrum signals, wherein the one or more generated spectrum signals vary based on an intensity ratio associated with the one or more radicals.
Optionally, the method comprises computing, by the controller, an amount of air and an amount of fuel to be supplied for combustion in a gas furnace based on the determined fuel composition.
Optionally, the one or more sensors comprise a light sensor operating in a range of 200-700nm, wherein the method comprises monitoring, by the light sensor, photons emitted from the flame emission.
Optionally, the one or more generated spectrum signals are chemiluminescence signals, the chemiluminescence signals indicative of electromagnetic radiations occurring or the photons generated due to transitions of the one or more radicals emitted during the fuel combustion.
Optionally, a first radical of the one or more radicals is an OH* radical and a second radical of the one or more radicals is a CH* radical, wherein the method comprises generating, by the first radical, the flame emission of a wavelength of 310nm, and generating, by the second radical, the flame emission of a wavelength of 430nm.
Optionally, the method comprises measuring, by the controller, the intensity ratio based on a ratio of the OH*/CH* radicals and correspondingly determining the fuel composition.
Optionally, the method comprises detecting, by the controller, upon detection of an increase in the flame emission associated with the OH* radical and/or the CH* radical, an increase in a flame temperature and a corresponding variation in the one or more spectrum signals.
Optionally, the method comprises detecting, by the controller, upon detection of a decrease in the flame emission associated with the OH* radical and/or the CH* radical, an increase in the amount of airflow available for the combustion, and a corresponding variation in the one or more spectrum signals.
Optionally, the method comprises actuating, by the controller, an inducer associated with the gas furnace to control the airflow into the gas furnace for combustion, based on the determined fuel composition.
Optionally, the method comprises actuating, by the controller, a gas valve associated with the gas furnace to control the amount of the fuel injected into the gas furnace based on the determined fuel composition.
The system(s) and method(s) disclosed herein also apply to residential and commercial boilers, as well as burners for industrial applications, and hence may be used therewith. Thus, according to another aspect of the invention there is provided a boiler and/or burner comprising the fuel identification and flame behaviour monitoring system as described herein with reference to the first aspect of the invention. The boiler may be a residential and/or commercial boiler. The burner may be for industrial applications. According to another aspect of the invention there is provided a method as recited herein with reference to the second aspect of the invention, comprising using a boiler and/or burner. The boiler may be a residential and/or commercial boiler. The burner may be for industrial applications.
The accompanying drawings are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification. The drawings illustrate exemplary embodiments of the invention and, together with the description, serve to explain the principles of the invention by way of example only.
In the drawings, similar components and/or features may have the same reference label. Further, various components of the same type may be distinguished by following the reference label with a second label that distinguishes among the similar components. If only the first reference label is used in the specification, the description is applicable to any one of the similar components having the same first reference label irrespective of the second reference label.

FIG. 1 illustrates an exemplary representation of a fuel identification and flame behavior monitoring system implemented in a gas furnace.
FIG. 2 illustrates an exemplary block diagram depicting functional modules of the system of FIG. 1.
FIG. 3 illustrates an exemplary method flow diagram of the fuel identification and flame behavior monitoring system.

The following is a detailed description of embodiments depicted in the accompanying drawings. The embodiments are in such detail as to clearly communicate the invention. However, the amount of detail offered is not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the invention as defined by the appended claims.
Various terms are used herein. To the extent a term used in a claim is not defined below, it should be given the broadest definition persons in the pertinent art have given that term as reflected in printed publications and issued patents at the time of filing.
Due to an increased drive to reduce carbon emissions, utilities are anticipated to blend renewable fuels or zero-carbon fuels such as Renewable Natural Gas (RNG), and Green Hydrogen, into their natural gas pipelines. This poses a challenge for safe furnace operation, as the addition of these fuels, above a certain limit, may significantly alter fuel composition and the amount of air to be mixed to achieve optimum combustion efficiency in a gas furnace. This impact may increase as the blending of fuel increases.
Further, during combustion, multiple chemical reactions may occur leading to the formation and destruction of intermediate species and radicals. Some of these species and radicals may be unstable at a higher energy level and emit photons, and further move to a more stable state. Each of these radicals may emit photons at a certain wavelength which enables identification of these radicals and their behavior/amount by a controller. An OH* radical chemiluminescence may be used in flame detection and control where the OH* emits photons at a wavelength band around 310nm (among others) and may be detected by ultraviolet (UV) sensors. Other radicals, such as CH* emit photons at a wavelength band around 430nm, which gives a blue color to a well-controlled flame. Further, other radicals may be emitted at various other wavelengths and may be identified by the controller. Hence, chemiluminescence emitted from OH* and CH* radicals may be utilized to determine the fuel composition of blended fuels.
Further, as the amount of excess air and flame temperature changes in the gas furnace based on the blended renewable fuel, or other factors, the emission of photons also changes. For OH*, the emission increases with an increase in flame temperature and decreases with an increase in the amount of excess air. The OH* amount also varies with fuel. As such, determining fuel type based on OH* on its own via a UV sensor may be insufficient, as the change in any of the factors such as temperature or excess air, among others, may impact the UV signal generated by the UV sensor. Furthermore, as the fuel composition changes, i.e., if the fuel used is switched from methane to propane, a higher CH* signal may be expected as a result of multiple CH bonds available in the fuel. However, if the fuel is switched from methane to hydrogen, the CH* signal may diminish as the amount of CH bond in the fuel is reduced. Detecting both radicals would furnish enough information to determine an underlying cause associated with the variation in the OH* and CH* signals. If the excess air or temperature are changed i.e., if lower excess air and higher flame temperature are observed, both OH* and CH* may be impacted and represented through the variation in the OH* and CH* signals. However, if the fuel is switched from methane (or natural gas) to hydrogen, OH* may increase while CH* may decrease, while the opposite may be observed when switching from methane (or natural gas) to propane.
There is therefore a need for a solution that detects both OH* and CH* signals to determine the composition of the fuel, as well as the amount of excess air based on an intensity ratio associated with the OH* and CH* radicals.
This disclosure provides a solution that determines the fuel composition based on the variation of the OH* and CH* signals, as these signals may vary based on an intensity ratio associated with the OH* and CH* radicals. This may offer solutions to customers while handling greener fuels (RNG/Green Hydrogen), and reduce Green House Gas (GHG) emissions, specifically when heat pumps are expensive or inefficient due to extreme climates. Further, this solution may help in handling unstable grids, or grids with high carbon dioxide (CO₂) emissions.
Referring to FIGs. 1 and 2, a fuel identification and flame behavior monitoring system 100 is disclosed. In one or more embodiments, the system 100 may be implemented in a gas furnace 104, however, the system 100 may also be implemented at other utilities where fuel combustion and flame behavior are to be monitored and controlled.
In one or more embodiments, the system 100 may include one or more sensors 102 that may be configured to monitor photons emitted from a flame emission during combustion of a fuel and correspondingly generate one or more spectrum signals associated with one or more radicals generated from the flame emission. The sensors 102 may comprise a light sensor operating in a range of 200-700nm, along with necessary filters for monitoring photons emitted from the flame emission at the desired bandwidths. The generated spectrum signals may be indicative of electromagnetic radiations occurring or the photons generated due to transitions of the one or more radicals emitted during the combustion. Further, the generated spectrum signals may be chemiluminescence signals based on photons emitted from the flame emission.
Alternatively, the system 100 may include two more sensors 102 that may be configured to monitor photons emitted, at two or more specific wavelength windows, from a flame emission during combustion of a fuel and correspondingly generate signals associated with each of the wavelength windows generated from the flame emission. The sensors 102 may comprise a light sensor operating in a range of 200-700nm along with necessary filters for monitoring photons emitted from the flame emission with the appropriate optical/wavelength filters at the desired bandwidths. The generated signals may be indicative of electromagnetic radiations occurring or the photons generated due to transitions of each of the radicals emitted during the combustion. Further, the generated signals may be chemiluminescence signals based on photons emitted from the flame emission.
In one or more embodiments, at least a first radical of the one or more radicals may be an OH radical (OH*) that generates the flame emission of a wavelength of 310nm. Further, at least a second radical of the one or more radicals may be a CH radical (CH*) that generates the flame emission of the wavelength of 430nm. Other radicals with emission windows at other wavelengths maybe also be utilized as needed.
In one or more embodiments, the system 100 may include a controller 200 that may be in communication with the sensors 102. The controller 200 may be configured to determine a fuel composition of the fuel based on a variation in the generated spectrum signals. The generated spectrum signals may vary based on an intensity ratio associated with the one or more radicals (OH* and CH*). The chemiluminescence signals or the generated spectrum signals may include intensity ratios between radicals OH*, CH* or other radicals, and maybe further corrected for broadband background radiation if needed. For example, the one or more radicals (OH*, CH*) may vary with excess air or flame temperature, among other factors, and hence the spectrum signals may vary based on the variations of the OH* and CH*radicals.
In one or more embodiments, the controller 200 may be configured to determine an amount of air and an amount of the fuel to be supplied for combustion based on the determined fuel composition. The controller 200 may be configured to monitor the combustion and flame behavior in a gas furnace 104 as illustrated in FIG. 1. Further, the controller 200 may be configured to measure the intensity ratio based on a ratio of the OH*/CH* radicals and correspondingly determine the fuel composition.
In one or more embodiments, upon detection of an increase in the flame emission associated with the OH* radical and/or the CH* radical, the controller 200 may detect an increase in a flame temperature and a corresponding variation in the spectrum signals. Upon detection of an increase in the flame temperature, the controller 200 may be configured to increase the airflow into the gas furnace for combustion based on the determined fuel composition. Further, upon detection of a decrease in the flame emission associated with the OH* radical and/or the CH* radical, the controller 200 may detect an increase in the amount of airflow available for the combustion and a corresponding variation in the spectrum signals. Upon detection of the increase in the amount of airflow available for the combustion, the controller 200 may be configured to actuate the gas valve to increase the amount of the fuel injected into the gas furnace based on the determined fuel composition, or increase the airflow into the gas furnace, if the gas valve was actuated correctly.
In one or more embodiments, an inducer associated with the gas furnace 104 may be operatively connected to the controller 200, where the controller 200 may be configured to actuate the inducer to control the airflow into the gas furnace 104 for combustion, based on the identified fuel composition. The inducer may be configured with a fuel injection system in the gas furnace 104. The controller 200, based on the determined fuel composition, may be configured to increase or decrease the inducer speed to change the amount of airflow to ensure that the combustion occurs safely and at an efficient point. For example, when the controller 200 detects that the fuel composition comprises a rich mixture, the controller 200 may actuate the inducer to increase the amount of airflow into the gas furnace to achieve optimum combustion.
In one or more embodiments, a gas valve associated with the gas furnace 104 may be operatively connected to the controller 200 and configured with the fuel injection system. The controller 200 may be configured to actuate the gas valve to control the amount of the fuel injected into the gas furnace 104 based on the determined fuel composition. The controller 200, based on the determined fuel composition, may be configured to control the gas valve to deliver the amount of fuel injected into the gas furnace, to ensure that the combustion occurs safely and at an efficient point, delivering thermal comfort to the end user. For example, when the controller 200 detects that the fuel composition comprises a lean mixture or a fuel with lower volumetric heat content, the controller may actuate the gas valve to increase the amount of the fuel injected into the gas furnace 104 to achieve optimum combustion and maintain the design firing rate.
In one or more embodiments, the fuel used in the gas furnace may include methane, where various percentages of hydrogen may be added to form a methane-hydrogen blended fuel. Here, CH* may significantly diminish with hydrogen addition, while OH* may be relatively constant. Accordingly, the spectrum signals may also vary with an equivalence ratio of the blended fuel. Further, the impact of fuel blends on the chemiluminescence emissions of CH*, OH* may be studied by the controller, and the response of the intensity ratio as a function of the equivalence ratio may be analyzed.
In one or more embodiments, the controller 200 may operate a furnace control board associated with the gas furnace 104 to determine the fuel composition and the amount of excess air within the gas furnace 104, which may be important for proper furnace operation. Based on these sensed values, the furnace control board may increase or decrease the inducer speed to change the amount of airflow and control the gas valve to furnish the desired fuel flow rate, ensuring that the combustion takes place safely and at the most efficient point.
Referring to FIG. 2, the controller 200 may include one or more processor(s) 202. The processor(s) 202 may be implemented as one or more microprocessors, microcomputers, microcontrollers, digital signal processors, central processing units, logic circuitries, and/or any devices that process data based on operational instructions. Among other capabilities, the processor(s) 202 may be configured to fetch and execute computer-readable instructions stored in a memory 204 of the controller 202. The memory 204 may be configured to store one or more computer-readable instructions or routines in a non-transitory computer-readable storage medium. Examples of such components include but are not limited to, a processing engine 208 and a database 210, where the processing engine 208 may include, but not be limited to, a data ingestion engine 212, and a control engine 214.
In an embodiment, the processing engine 208 may be implemented as a combination of hardware and programming (for example, programmable instructions) to implement one or more functionalities of the processing engine 208. In examples described herein, such combinations of hardware and programming may be implemented in several different ways. For example, the programming for the processing engine 208 may be processor-executable instructions stored on a non-transitory machine-readable storage medium and the hardware for the processing engine 208 may comprise a processing resource (for example, one or more processors), to execute such instructions.
In an embodiment, the fuel identification and flame behavior monitoring system 100 may include an interface 206. The interface 206 may comprise a variety of interfaces, for example, interfaces for data input and output (I/O) devices, storage devices, and the like. The interface 206 may also provide a communication pathway for one or more components of the system 100.
In one or more embodiments, the controller 200 may be configured to determine a fuel composition of a fuel based on a variation in one or more generated spectrum signals using the processing engine 208. The data ingestion engine 212, upon execution, may enable controller 200 to receive data from the sensors 102. The controller 200 may store the information in the database 210. The generated spectrum signals may vary based on an intensity ratio associated with one or more radicals (OH* and CH*). The generated spectrum signals may be chemiluminescence signals that include intensity ratios between radicals OH*, CH*, C*₂ (at 310, 430 and 517 nm, respectively) or CO*₂. For example, when the fuel identification and flame behavior monitoring system 100 is implemented in a gas furnace, the one or more radicals (OH*, CH*) may vary with excess air or flame temperature, among others. Hence, the spectrum signals may vary based on the variations of the OH* and CH*radicals.
In one or more embodiments, the controller 200 may be configured to determine an amount of air and an amount of the fuel to be supplied for combustion based on the determined fuel composition. The controller 200 may be configured to measure the intensity ratio based on a ratio of the OH*/CH* radicals and correspondingly determine the fuel composition.
In one or more embodiments, upon detection of an increase in the flame emission associated with the OH* radical and /or the CH* radical, the controller 200 may detect an increase in a flame temperature and a corresponding variation in the spectrum signals. Further, upon detection of a decrease in the flame emission associated with the OH* radical, and/or the CH* radical, the controller 200 may detect an increase in the amount of airflow available for the combustion and a corresponding variation in the spectrum signals.
In one or more embodiments, the control engine 214, upon execution, may enable the controller to actuate an inducer associated with the gas furnace 104 to control the airflow into the gas furnace 104 for combustion, based on the identified fuel composition. The inducer may be configured with a fuel injection system in the gas furnace 104.
Further, in one or more embodiments, the control engine 214, upon execution, may enable actuate the gas valve to control the amount of the fuel injected into the gas furnace 104 based on the determined fuel composition.
In one or more embodiments, referring to FIG. 3, the method flow diagram of the fuel identification and flame behavior monitoring system 100 may include the following steps.
At step 302, method 300 may include monitoring, by the controller 200, photons emitted from a flame emission and correspondingly generating one or more spectrum signals associated with one or more radicals generated from the flame emission.
At step 304, method 300 may include determining, by the controller 200, a fuel composition of a fuel based on a variation in the one or more generated spectrum signals, where the one or more generated spectrum signals may vary based on an intensity ratio associated with the one or more radicals.
Thus, this disclosure (system and method) provides an efficient and reliable solution that determines the fuel composition and flame behavior based on the variation of the chemiluminescence signals associated with OH* and CH* emitted during the combustion of fuel, as these signals may vary based on an intensity ratio associated with the OH* and CH* radicals.
While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention as defined by the appended claims. Modifications may be made to adopt a particular situation or material to the teachings of the invention without departing from the scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiment disclosed, but that the invention includes all embodiments falling within the scope of the invention as defined by the appended claims.
In interpreting the specification, all terms should be interpreted in the broadest possible manner consistent with the context. In particular, the terms "comprises" and "comprising" should be interpreted as referring to elements, components, or steps in a non-exclusive manner, indicating that the referenced elements, components, or steps may be present, or utilized, or combined with other elements, components, or steps that are not expressly referenced. Where the specification claims refer to at least one of something selected from the group consisting of A, B, C ....and N, the text should be interpreted as requiring only one element from the group, not A plus N, or B plus N, etc.
The following clauses recite features of the invention that may or may not currently be claimed, and which may serve as basis for amendment, and/or one or more divisional application:

1. A fuel identification and flame behavior monitoring system, the system comprising:
- a plurality of sensors configured to monitor photons emitted from a flame emission during combustion of a fuel and correspondingly generate one or more spectrum signals associated with a plurality of radicals generated from the flame emission; and
- a controller in communication with the plurality of sensors, the controller configured to:
  determine a fuel composition of the fuel based on a variation in the one or more generated spectrum signals, wherein the one or more generated spectrum signals vary with an intensity ratio associated with the plurality of radicals.
2. The system of clause 1, wherein the controller is configured to compute an amount of air and an amount of the fuel to be supplied in a gas furnace for combustion of the fuel therein based on the determined fuel composition.
3. The system of any one of clauses 1 and 2, wherein the one or more sensors comprise a light sensor operating in a range of 200-700nm, for monitoring photons emitted from the flame emission.
4. The system of any one of clauses 1 to 3, wherein the one or more generated spectrum signals are chemiluminescence signals indicative of electromagnetic radiations occurring or the photons generated due to transitions of the plurality of radicals emitted during the fuel combustion.
5. The system of any one of clauses 1 to 4, wherein at least a first radical of the plurality of radicals is an OH* radical that generates the flame emission of a wavelength of 310nm, and a second radical of the plurality of radicals is a CH* radical that generates the flame emission of a wavelength of 430nm.
6. The system of clause 5, wherein the controller is configured to measure the intensity ratio based on a ratio of the OH*/CH* radicals and correspondingly determine the fuel composition.
7. The system of clause 5, wherein upon detection of an increase in the flame emission associated with the OH* radical and/or the CH* radical, the controller detects an increase in a flame temperature and a corresponding variation in the one or more spectrum signals.
8. The system of clause 5, wherein upon detection of a decrease in the flame emission associated with the OH* radical and/or the CH* radical, the controller detects an increase in the amount of airflow available for the combustion and a corresponding variation in the one or more spectrum signals.
9. The system of clause 2, wherein an inducer associated with the gas furnace is operatively connected to the controller, wherein the controller is configured to actuate the inducer to control the airflow into the gas furnace for combustion, based on the determined fuel composition.
10. The system of clause 2, wherein a gas valve associated with the gas furnace is operatively connected to the controller, wherein the controller is configured to actuate the gas valve to control the amount of the fuel injected into the gas furnace based on the determined fuel composition.
11. A method for fuel identification and flame behavior monitoring, the method comprising:
- monitoring, by a controller, photons emitted from a flame emission during combustion of a fuel and correspondingly generating one or more spectrum signals associated with a plurality of radicals generated from the flame emissions; and
- determining, by the controller, a fuel composition of the fuel based on a variation in the one or more generated spectrum signals, wherein the one or more generated spectrum signals vary with an intensity ratio associated with the plurality of radicals.
12. The method of clause 11, comprising computing, by the controller, an amount of air and an amount of the fuel to be supplied for combustion in a gas furnace based on the determined fuel composition.
13. The method of any one of clauses 11 and 12, comprising using by the one or more sensors, a light sensor operating in a range of 200-700nm, for monitoring photons emitted from the flame emission.
14. The method of any one of clauses 11 to 13, comprising indicating, by the one or more generated spectrum signals that are chemiluminescence signals, electromagnetic radiations occurring or the photons generated due to transitions of the plurality of radicals emitted during the combustion.
15. The method of any one of clauses 11 to 14, comprising:
- generating, by at least a first radical of the plurality of radicals, an OH* radical the generates the flame emission of a wavelength of 3 10nm; and
- generating, by a second radical of the plurality of radicals, a CH* radical that generates the flame emission of the wavelength of 430nm.
16. The method of clause 15, comprising measuring, by the controller, the intensity ratio based on a ratio of the OH*/CH* radicals and correspondingly determining the fuel composition.
17. The method of clause 15, comprising detecting, by the controller, based on a detection of an increase in the flame emission associated with the OH* radical and/or the CH* radical, an increase in a flame temperature and a corresponding variation in the one or more spectrum signals.
18. The method of clause 15, comprising detecting, by the controller, based on a detection of a decrease in the flame emission associated with the OH* radical and/or the CH* radical, an increase in the amount of airflow available for the combustion and a corresponding variation in the one or more spectrum signals.
19. The method of any one of clauses 11 to 18, comprising actuating, by the controller, an inducer to control the airflow into the gas furnace for combustion, based on the determined fuel composition.
20. The method of any one of clauses 11 to 19, comprising actuating, by the controller, a gas valve to control the amount of the fuel injected into the gas furnace based on the determined fuel composition.

Claims

A fuel identification and flame behavior monitoring system, the system comprising:
one or more sensors configured to monitor photons emitted from a flame emission during combustion of a fuel and correspondingly generate one or more spectrum signals associated with one or more radicals generated from the flame emission; and

a controller in communication with the one or more sensors, the controller configured to:
determine a fuel composition of the fuel based on a variation in the one or more generated spectrum signals, wherein the one or more generated spectrum signals vary based on an intensity ratio associated with the one or more radicals.
The system of claim 1, wherein the controller is further configured to determine an amount of air and an amount of fuel to be supplied in a gas furnace for combustion of the fuel therein based on the determined fuel composition.
The system of claim 1 or 2, wherein the one or more sensors comprise a light sensor operating in a range of 200-700nm, for monitoring photons emitted from the flame emission.
The system of claim 1, 2 or 3, wherein the one or more generated spectrum signals are chemiluminescence signals indicative of electromagnetic radiations occurring or photons generated due to transitions of the one or more radicals emitted during the fuel combustion.
The system of any preceding claim, wherein at least a first radical of the one or more radicals is an OH* radical that generates the flame emission of a wavelength of 3 10nm, and a second radical of the one or more radicals is a CH* radical that generates the flame emission of a wavelength of 430nm.
The system of claim 5, wherein the controller is further configured to measure the intensity ratio based on a ratio of the OH*/CH* radicals and correspondingly determine the fuel composition.
The system of claim 5 or 6, wherein upon detection of an increase in the flame emission associated with the OH* radical and/or the CH* radical, the controller is configured to detect an increase in a flame temperature and a corresponding variation in the one or more spectrum signals; and/or
wherein upon detection of a decrease in the flame emission associated with the OH* radical and/or the CH* radical, the controller is configured to detect an increase in the amount of airflow available for the combustion and a corresponding variation in the one or more spectrum signals.
The system of any of claims 2 to 7, wherein an inducer associated with the gas furnace is operatively connected to the controller, and wherein the controller is further configured to actuate the inducer to control airflow into the gas furnace for combustion, based on the determined fuel composition; and/or
wherein a gas valve associated with the gas furnace is operatively connected to the controller, and wherein the controller is further configured to actuate the gas valve to control the amount of the fuel injected into the gas furnace based on the determined fuel composition.
A method for fuel identification and flame behavior monitoring, the method comprising:
monitoring, by one or more sensors, photons emitted from a flame emission during combustion of a fuel and correspondingly generating one or more spectrum signals associated with one or more radicals generated from the flame emission; and

determining, by a controller, a fuel composition of the fuel based on a variation in the one or more generated spectrum signals, wherein the one or more generated spectrum signals vary based on an intensity ratio associated with the one or more radicals.
The method of claim 9, further comprising determining, by the controller, an amount of air and an amount of fuel to be supplied for combustion in a gas furnace based on the determined fuel composition.
The method of claim 9 or 10, wherein the one or more sensors comprise a light sensor operating in a range of 200-700nm, and wherein the method comprises monitoring, by the light sensor, photons emitted from the flame emission.
The method of claim 9, 10 or 11, wherein the one or more generated spectrum signals are chemiluminescence signals, the chemiluminescence signals indicative of electromagnetic radiations occurring or photons generated due to transitions of the one or more radicals emitted during the fuel combustion.
The method of any of claims 9 to 12, wherein a first radical of the one or more radicals is an OH* radical, wherein a second radical of the one or more radicals is CH* radical, and wherein the method further comprises:
generating, by the first radical, the flame emission of a wavelength of 310nm; and

generating, by the second radical, the flame emission of a wavelength of 430nm; and
optionally, further comprising measuring, by the controller, the intensity ratio based on a ratio of the OH*/CH* radicals and correspondingly determining the fuel composition.
The method of claim 13, further comprising detecting, by the controller, upon detection of an increase in the flame emission associated with the OH* radical and/or the CH* radical, an increase in a flame temperature and a corresponding variation in the one or more spectrum signals; and/or
comprising detecting, by the controller, upon detection of a decrease in the flame emission associated with the OH* radical and/or the CH* radical, an increase in the amount of airflow available for the combustion and a corresponding variation in the one or more spectrum signals.
The method of any of claims 9 to 14, further comprising actuating, by the controller, an inducer associated with the gas furnace to control airflow into the gas furnace for combustion, based on the determined fuel composition; and/or
further comprising actuating, by the controller, a gas valve associated with the gas furnace to control the amount of the fuel injected into the gas furnace based on the determined fuel composition.