A boiler coal saving control method includes a linear relation model creating step, an optimization target determination step, and a machine learning step. The linear relation model creating step includes creating a multi-grade model grading mechanism and creating linear relation models accordingly so as to fill an empty set in a data set. The multi-grade model grading mechanism includes performing primary grading based on boiler load, coal quality, and ambient temperature, and secondary grading based on boiler load. The optimization target determination step includes determining a boiler optimization target that includes boiler combustion efficiency and a nitrate concentration control value for flue gas. The machine learning step performs machine learning according to a data source and includes a model numbering sub-step, an ontology determination sub-step, and a target optimization sub-step. The control method uses machine learning to provide an operation recommendation for improving boiler combustion efficiency and thereby saving coal.

In a method for estimating water content of exhaust gas, a first gas concentration at a first position in an exhaust passage, a second gas concentration at a second position downstream of the first position, and a gas temperature at the second position are obtained. A saturated water vapor at the gas temperature is calculated as a water content at the second position. By using the water content at the second position and the second gas concentration, an excess air amount of a fuel-air mixture supplied to a combustion apparatus is calculated based on a chemical reaction formula of combustion of the mixture. By using the excess air amount and the first gas concentration, a water content at the first position is estimated.

Methods and systems for resonance suppression, can involve measuring signals with one or more sensors, wherein the signals are produced by a combustor associated with an actuator, and receiving at a controller the signals measured by the sensor or sensors. The controller can calculate a damping rate of the combustor. Based on the damping rate, the controller can modulate the actuator if the damping rate falls below a predefined threshold and can continue to modulate the actuator until the damping rate is adjusted and the resonance is suppressed. The sensor can be an acoustic sensor, an optical sensor, or another type of sensor.

The method may include retrieving a first cooking profile associated with the first food item, wherein the first cooking profile comprises at least one first temperature set point and at least one first time period. The method may also include controlling a temperature of the grill to the first cooking profile. The method may further include retrieving a second cooking profile associated with a second food item, wherein the second cooking profile comprises at least one second temperature set point and at least one second time period. The method may also include combining the first cooking profile and the second cooking profile to form a hybrid cooking profile comprising at least one third temperature set point and at least one third time period. The method may further include controlling the grill to the hybrid cooking profile after beginning the second cooking session.

Methods and systems for resonance suppression, can involve measuring signals with one or more sensors, wherein the signals are produced by a combustor associated with an actuator, and receiving at a controller the signals measured by the sensor or sensors. The controller can calculate a damping rate of the combustor. Based on the damping rate, the controller can modulate the actuator if the damping rate falls below a predefined threshold and can continue to modulate the actuator until the damping rate is adjusted and the resonance is suppressed. The sensor can be an acoustic sensor, an optical sensor, or another type of sensor.

Methods for regulating a heating device, which includes a combustion chamber, into which combustion air is introduced via a controllable blower. An operating variable and a speed of the blower are measured. An operating coefficient is determined on the basis of the measured operating variable and the measured speed. A volume flow coefficient is determined on the basis of reference values for the operating coefficient. A volume flow of the combustion air being determined on the basis of the volume flow coefficient. A calibration of the reference values is carried out for the operating coefficient.

A controller for a gas turbine arranged to supply a load is described. The gas turbine includes a fuel supply arranged to supply fuel at a fuel flow rate to a combustor. The fuel supply includes a first fuel supply and a second fuel supply. The controller is arranged to control a proportion of the fuel flow rate supplied via the first fuel supply based, at least in part, on the fuel flow rate. A gas turbine includes such a controller and a method controls such a gas turbine.

A flame sensor assembly includes a flame sense rod and a flame sensor body. The flame sense rod includes a flame sensor end and a coupling end opposite the flame sensor. The flame sensor body defines a receptacle for receiving the coupling end of the flame sense rod, and includes an adjustable positioning bracket. The assembly also includes a wiring adapter for connecting the flame sensor body with a flame sense signal connector, and a mounting bracket adapted to mount the flame sensor body to a heating device with the flame sensor end of the flame sense rod positioned adjacent a flame of the heating device. Methods of replacing a flame sensor assembly for a heating device are also disclosed.

An electronic control device includes: a flow rate calculation unit that calculates a flow rate of intake air based on an output signal of a flow rate measurement device assembled to an intake pipe; a flow rate correction value calculation unit that calculates an average value, a maximum value, and a minimum value of the flow rate of the intake air, calculated by the flow rate calculation unit, during a predetermined period, and an amplitude of a signal with one or more frequencies equal to or higher than a fundamental frequency of the output signal of the flow rate measurement device and included in the output signal of the flow rate measurement device, and calculates a correction value for the flow rate of the intake air based on calculation results; and a flow rate correction unit that corrects the flow rate of the intake air based on the correction value.

Disclosed is an induced-draft gas-fired furnace that includes: an electronic furnace controller, a burner assembly, a gas valve, and an inducer motor, wherein the controller: accelerates the inducer motor at a first pre-ignition rate to a first pre-ignition speed; controls the gas valve to supply gas to the burner assembly to obtain a first pre-ignition ratio of fuel to air, operates an igniter to attempt to ignite the first fuel mixture, determines whether fuel has ignited in the burner assembly, wherein when fuel having the first pre-ignition ratio of fuel to air remains unignited after a plurality of ignition attempts, the controller: decelerates the inducer motor to a second pre-ignition rate to obtain a second pre-ignition speed and a second fuel mixture comprising a second pre-ignition ratio of fuel to air, and determines whether the second fuel mixture has ignited in the burner assembly.