Combustion system with automated control of primary and secondary airflows

Abstract

A combustion system includes sensor, an exhaust sensor, a primary actuator associated with primary airflow, a secondary actuator associated with secondary airflow, and a processor. When the combustion system is in at least one of an initiation phase or an initiation transition phase, the processor is configured to control primary actuator and the secondary actuator based on an initiation configuration. The processor is further configured to determine a transition of the combustion system to an equilibrium phase based at least in part on: a comparison of a chamber temperature measurement received from the chamber sensor with a chamber endothermic setpoint; and a comparison of an exhaust temperature measurement received from the exhaust sensor with an exhaust ignition setpoint. When the combustion system is in the equilibrium phase, the processor is configured to control the primary actuator and the secondary actuator based on an equilibrium configuration.

1 . A method for controlling a combustion system comprising a chamber sensor, an exhaust sensor, a primary actuator associated with primary airflow, a secondary actuator associated with secondary airflow, and at least one processor in communication with the chamber sensor, the exhaust sensor, the primary actuator and the secondary actuator, the method comprising:
 when the combustion system is in at least one of an initiation phase or an initiation transition phase, controlling, with the at least one processor, the primary actuator and the secondary actuator based on an initiation configuration;   determining, with the at least one processor, a transition of the combustion system to an equilibrium phase based at least in part on:
 a comparison of at least one chamber temperature measurement received from the chamber sensor with a chamber endothermic setpoint; and 
 a comparison of at least one exhaust temperature measurement received from the exhaust sensor with an exhaust ignition setpoint; and 
   when the combustion system is in the equilibrium phase, controlling, with the at least one processor, the primary actuator and the secondary actuator based on an equilibrium configuration.   
     
     
         2 . The method of  claim 1 , wherein determining the transition to the equilibrium phase further comprises determining that the transition to the equilibrium phase has occurred when the at least one chamber temperature measurement is greater than the chamber endothermic setpoint. 
     
     
         3 . The method of  claim 1 , wherein controlling the primary actuator and the secondary actuator based on the initiation configuration comprises:
 controlling the primary actuator based at least in part on a primary comparison of the at least one chamber temperature measurement with the chamber endothermic setpoint; and   controlling the secondary actuator based at least in part on a secondary comparison of the at least one exhaust temperature measurement with an exhaust upper setpoint and an exhaust lower setpoint.   
     
     
         4 . The method of  claim 1 , wherein controlling the primary actuator and the secondary actuator based on the equilibrium configuration comprises:
 controlling the primary actuator based on a primary comparison of at least one chamber temperature measurement received from the chamber sensor with the chamber endothermic setpoint; and   controlling the secondary actuator based on an equilibrium secondary comparison of at least one exhaust temperature measurement received from the exhaust sensor with an exhaust upper setpoint and an exhaust lower setpoint.   
     
     
         5 . The method of  claim 1 , further comprising setting, with the at least one processor, a termination event flag during the equilibrium phase based at least in part on the at least one chamber temperature measurement is greater than a sum of the chamber endothermic setpoint and a chamber termination value. 
     
     
         6 . The method of  claim 5 , further comprising at least one of:
 determining, with the at least one processor, a transition from the equilibrium phase to a termination transition phase; or   determining, with the at least one processor, a transition from the termination transition phase to a termination phase.   
     
     
         7 . The method of  claim 6 , wherein determining the transition from the equilibrium phase to the termination transition phase comprises:
 determining, with the at least one processor, whether the termination event flag has been set;   comparing, with the at least one processor, at least one current chamber temperature measurement received from the chamber sensor with, at least, at least one previous chamber temperature measurement received from the chamber sensor;   comparing, with the at least one processor, at least one current exhaust temperature measurement received from the exhaust sensor with, at least, at least one previous exhaust temperature measurement received from the exhaust sensor; and   determining, with the at least one processor, that the transition to the termination transition phase has occurred based at least in part on the termination event flag being set, the at least one current chamber temperature measurement being less than the at least one previous chamber temperature measurement, and the at least one current exhaust temperature measurement being less than the at least one previous exhaust temperature measurement.   
     
     
         8 . The method of  claim 7 , further comprising, when the combustion system is in the termination transition phase, controlling, with the at least one processor, the primary actuator and the secondary actuator based on a termination initiation configuration. 
     
     
         9 . The method of  claim 8 , wherein controlling the primary actuator and the secondary actuator based on the termination initiation configuration comprises controlling, with the at least one processor, the secondary actuator and the primary actuator based at least in part on a comparison of at least one chamber temperature measurement received from the chamber sensor with the chamber endothermic setpoint. 
     
     
         10 . The method of  claim 7 , further comprising, when the combustion system is in the termination phase, controlling, with the at least one processor, the secondary actuator and the primary actuator based on a termination configuration. 
     
     
         11 . The method of  claim 10 , wherein controlling the secondary actuator and the primary actuator based on the termination configuration comprises controlling the secondary actuator and the primary actuator based at least in part on a comparison of at least one chamber temperature measurement received from the chamber sensor with a chamber under-zone setpoint. 
     
     
         12 . The method of  claim 1 , further comprising at least one of:
 determining, with the at least one processor, a transition into the initiation phase; and   determining, with the at least one processor, a transition from the initiation phase to the initiation transition phase.   
     
     
         13 . The method of  claim 12 , wherein determining the transition into the initiation phase comprises determining whether an ignition event has occurred. 
     
     
         14 . The method of  claim 11 , wherein determining the transition from the initiation phase to the initiation transition phase comprises:
 comparing, with the at least one processor, at least one chamber temperature measurement received from the chamber sensor with at least a chamber ignition setpoint;   comparing, with the at least one processor, the at least one exhaust temperature measurement received from the exhaust sensor with at least the exhaust ignition setpoint; and   determining, with the at least one processor, that the transition to the initiation transition phase has occurred when the at least one chamber temperature measurement is greater than the chamber ignition setpoint and the at least one exhaust temperature measurement is greater than the exhaust ignition setpoint.   
     
     
         15 . A method for reducing emissions of a combustion system comprising a chamber and an exhaust coupled to the chamber, the method comprising:
 directing a first portion of airflow within the chamber to pass through a catalyst coupled to a top wall of the chamber before entering an opening of the exhaust, wherein the catalyst covers a catalyst portion of the opening and wherein the catalyst is coupled to the top wall at an angle relative to a plane of the opening; and   directing a second portion of the airflow entering the opening without passing through the catalyst, wherein the catalyst does not cover a bypass portion of the opening.   
     
     
         16 . The method of  claim 15 , wherein the catalyst portion of the opening is at least 60% of a total area of the opening. 
     
     
         17 . A combustion system comprising:
 a chamber;   an exhaust coupled to the chamber, the exhaust having a catalyst portion of an opening of the exhaust and a bypass portion of the opening of the exhaust; and   a catalyst coupled to a top wall of the chamber proximate to the opening of the exhaust, wherein the catalyst covers the catalyst portion of the opening to permit a first portion of air exiting the chamber to pass through the catalyst before entering an opening of the exhaust while a second portion of airflow enters the opening by the bypass portion without passing through the catalyst.   
     
     
         18 . The combustion system of  claim 17 , wherein the bypass portion of the opening is at least 35% of a total area of the opening. 
     
     
         19 . The combustion system of  claim 17 , wherein the catalyst is coupled to the top wall at an angle relative to a plane of the opening. 
     
     
         20 . The combustion system of  claim 19 , wherein the angle is 12.5°.