A combustion system is capable of using a petroleum pitch fuel, and is provided with a burner having a fuel supply pipe where a flame stabilizing plate is formed in a tip end of the same, and a high temperature maintaining unit for maintaining an atmosphere temperature at a vicinity of the flame stabilizing plate during operation higher than a softening point of the petroleum pitch fuel. Thus, even when the petroleum pitch is used as fuel, the burner does not become unusable due to adhesion/solidification of the petroleum pitch inside the burner and combustion operation can be continued for a long time.

An air handling unit (AHU) for a heating, ventilation, air conditioning, and refrigeration (HVACR) system includes a housing and a combustion heater disposed within the housing. The housing includes a combustion section with a first channel and a second channel. The combustion heater includes heat exchanger tubes and a tube support that supports heat exchanger tubes within the combustion section. The tube support slidably disposed in the first channel and the second channel. The combustion heater configured to be slidably removable from the AHU. An AHU for an HVACR system includes a housing with a fan section and a fan assembly disposed within the housing. The fan assembly including a pair of grooves slidably disposed on a pair of rails of the housing. The fan assembly configured to be both slidably removable from the AHU and liftably removable from the AHU.

A fuel supply system for a gas burner assembly. The gas burner assembly includes an inner burner stage positioned concentrically within an outer burner stage. The fuel supply system includes a fuel supply for providing a primary flow of fuel through a primary fuel conduit and a single outlet control valve operably coupled to the primary fuel conduit. A first and second fuel supply conduit split off of the primary fuel conduit and are fluidly coupled with the outer burner stage and the inner burner stage, respectively. A shutoff valve is operably coupled to one of the first fuel supply conduit and the second fuel supply conduit and is configured for closing when a flow rate of fuel through the shutoff valve drops below a predetermined flow rate.

A premix burner made up of an air inlet tube of length L and a single specific gas injection, the gas injection includes an upstream gas injector, a mixer, a downstream gas injection situated at a distance L3 from an upstream end of the air inlet tube and a stabilizing element, where the gas injection constitutes a one-piece mechanical assembly that ensures a self-stable elementary flame.

A method for detecting flameholding in at least one combustor of a turbine engine includes measuring dynamic pressure data of the at least one combustor of the turbine engine; converting the dynamic pressure data to frequency-domain spectral energy amplitudes for the dynamic pressure data; and comparing the spectral energy amplitudes against a dynamic amplitude threshold value to determine whether the amplitudes exceed the threshold minimum amplitude value, wherein exceeding the dynamic amplitude threshold indicates a flameholding occurrence.

A method for detecting flameholding in at least one combustor of a turbine engine includes measuring dynamic pressure data of the at least one combustor of the turbine engine; converting the dynamic pressure data to frequency-domain spectral energy amplitudes for the dynamic pressure data; and comparing the spectral energy amplitudes against a dynamic amplitude threshold value to determine whether the amplitudes exceed the threshold minimum amplitude value, wherein exceeding the dynamic amplitude threshold indicates a flameholding occurrence.

An air handling unit (AHU) for a heating, ventilation, air conditioning, and refrigeration (HVACR) system includes a housing and a combustion heater disposed within the housing. The housing includes a combustion section with a first channel and a second channel. The combustion heater includes heat exchanger tubes and a tube support that supports heat exchanger tubes within the combustion section. The tube support slidably disposed in the first channel and the second channel. The combustion heater configured to be slidably removable from the AHU. An AHU for an HVACR system includes a housing with a fan section and a fan assembly disposed within the housing. The fan assembly including a pair of grooves slidably disposed on a pair of rails of the housing. The fan assembly configured to be both slidably removable from the AHU and liftably removable from the AHU.

A cooktop appliance includes a top panel that defines an opening. A first gas burner is positioned on the top panel at the opening of the top panel. A second gas burner includes a burner body, a horizontal mixing tube and a fuel orifice. The burner body is positioned on the top panel away from the opening of the top panel. The horizontal mixing tube is positioned below the top panel and extends between the burner body and the fuel orifice. The fuel orifice is positioned below the top panel at the opening of the top panel.

A fuel supply system for a gas burner assembly is provided. The gas burner assembly includes an inner burner stage positioned concentrically within an outer burner stage. The fuel supply system includes a fuel supply for providing a primary flow of fuel through a primary fuel conduit and a single outlet control valve operably coupled to the primary fuel conduit. A first and second fuel supply conduit split off of the primary fuel conduit and are fluidly coupled with the outer burner stage and the inner burner stage, respectively. A shutoff valve is operably coupled to one of the first fuel supply conduit and the second fuel supply conduit and is configured for closing when a flow rate of fuel through the shutoff valve drops below a predetermined flow rate.

An inlet assembly for a burner and a method are disclosed. The inlet assembly comprises: an inlet nozzle defining an inlet aperture coupleable with an inlet conduit providing an effluent gas stream for treatment by the burner, a non-circular outlet aperture, and a nozzle bore extending along a longitudinal axis between the inlet aperture and the outlet aperture for conveying the effluent gas stream from the inlet aperture to the outlet aperture for delivery to the combustion chamber of the burner, the nozzle bore having an inlet portion extending from the inlet aperture and an outlet portion extending to the non-circular outlet aperture. In this way, the non-circular outlet aperture provides a non-circular effluent gas stream flow into the combustion chamber. The non-circular effluent gas flow enables a greater volume of effluent gas stream to be introduced into the combustion chamber whilst still achieving or exceeding the required levels of abatement. This is because a non-circular effluent gas stream provides a reduced distance along which diffusion and reaction needs to occur compared to that of an equivalent circular effluent gas stream. Hence, an increased volume of effluent gas stream can be abated, compared to that of an equivalent circular effluent gas stream.