Combustion system for solid biomass fuel

A combustor system, the system comprising:

• an inner wall defining a combustion chamber, the inner wall having a longitudinal axis, a first end, and a second end opposite and spaced apart from the first end along the longitudinal axis, wherein the inner wall defines one or more primary air inlets and one or more secondary air inlets spaced apart from the one or more primary air inlets along the longitudinal axis, wherein the one or more primary air inlets are defined closer than the one or more secondary air inlets to the first end of the inner wall;
• a fuel grate disposed within the combustion chamber between the one or more primary air inlets and the one or more secondary air inlets, the fuel grate configured to support fuel disposed within the combustion chamber, wherein the fuel grate defines one or more grate openings;
• an ash grinder disposed within the combustion chamber between the fuel grate and the one or more secondary air inlets, the ash grinder having at least one radially extending protrusion, wherein the ash grinder is rotatable about the longitudinal axis relative to the fuel grate;
• an igniter for providing energy to a portion of the combustion chamber between the fuel grate and the one or more secondary air inlets;
• a fan configured to cause air to flow through the one or more primary air inlets and the one or more secondary air inlets, into the combustion chamber, and through the second end of the combustion chamber;
• a processor in electrical communication with a system memory, wherein the processor executes computer-readable instructions stored on the system memory to control the fan and the ignitor, wherein the igniter comprises an air igniter;
• and
• at least one actuator and at least one valve configured to vary the air flow through the one or more primary air inlets, the one or more secondary air inlets, and the air igniter, wherein during an ignition phase, the processor causes the at least one actuator to periodically alternate between allowing air to flow through the one or more primary air inlets and the one or more secondary air inlets and allowing air to flow through the air igniter.