A combustor for a detonation engine includes a radially outer wall extending along an axis; a radially inner wall extending along the axis, wherein the radially inner wall is positioned at least partially within the radially outer wall to define an annular detonation chamber having an inlet for fuel and oxidant and an outlet; a cooling flow passage defined along at least one of the radially outer wall and the radially inner wall and comprising at least two axially spaced cooling flow passage sections, whereby a different cooling rate can be implemented in the at least two axially spaced cooling flow passage sections.

A pulse combustion heat exchanger having a longitudinal axis is configured to accept oxidant and fuel and output a cooled combustion stream. The pulse combustion heat exchanger includes an oxidant inlet section that accepts oxidant, a fuel inlet section that accepts fuel, a mixing section that mixes oxidant with fuel, a combustion section that receives the oxidant and fuel and produces a pulsating combustion stream, and a heat transfer section configured to receive the pulsating combustion stream, the heat transfer section includes one or more resonance conduits. Coolant is employed at a plurality of longitudinally spaced-apart transition sections to remove heat.

A pulse combustion heat exchanger having a longitudinal axis is configured to accept oxidant and fuel and output a cooled combustion stream. The pulse combustion heat exchanger includes an oxidant inlet section that accepts oxidant, a fuel inlet section that accepts fuel, a mixing section that mixes oxidant with fuel, a combustion section that receives the oxidant and fuel and produces a pulsating combustion stream, and a heat transfer section configured to receive the pulsating combustion stream, the heat transfer section includes one or more resonance conduits. Coolant is employed at a plurality of longitudinally spaced-apart transition sections to remove heat.

A scalable pulse combustor that can be deployed as the heat exchanger in high efficiency, low NOx condensing boilers, water heaters and steam generators is provided. The combustor generally comprises an annular burner coil with a burner flange for accommodating the nozzle of a conventional burner/blower fitted into the central aperture thereof; a spaced-apart opposite annular spreader coil with a heat exchange hub fitted into the central aperture thereof; and a plurality of annular intermediate coils. Each of the burner, spreader and intermediate coils are preferably formed of spiral wound stainless steel tubing, with each winding directly abutting the preceding winding so as to create an annular wall. The heat exchange hub functions as a secondary heat exchanger with its own independently controllable coolant flow.

A pulse combustion heat exchanger having a longitudinal axis is configured to accept oxidant and fuel and output a cooled combustion stream. The pulse combustion heat exchanger includes an oxidant inlet section that accepts oxidant, a fuel inlet section that accepts fuel, a mixing section that mixes oxidant with fuel, a combustion section that receives the oxidant and fuel and produces a pulsating combustion stream, and a heat transfer section configured to receive the pulsating combustion stream, the heat transfer section includes one or more resonance conduits. Coolant is employed at a plurality of longitudinally spaced-apart transition sections to remove heat.

A pulse combustion heat exchanger having a longitudinal axis is configured to accept oxidant and fuel and output a cooled combustion stream. The pulse combustion heat exchanger includes an oxidant inlet section that accepts oxidant, a fuel inlet section that accepts fuel, a mixing section that mixes oxidant with fuel, a combustion section that receives the oxidant and fuel and produces a pulsating combustion stream, and a heat transfer section configured to receive the pulsating combustion stream, the heat transfer section includes one or more resonance conduits. Coolant is employed at a plurality of longitudinally spaced-apart transition sections to remove heat.

An acoustic compression engine that includes an air intake section adapted to intake a volume of air. The volume of air is mixed with fuel within the air intake section. The acoustic compression engine also includes a resonant chamber adapted to intake a volume of air mixed with fuel from the air intake section. Compression of the volume of air mixed with fuel occurs within the resonant chamber and compression of the volume of air and fuel mixture is based on combustion of compressed air and fuel mixture and a resonant cycle of the acoustic compression engine. The acoustic compression engine further includes at least one exhaust nozzle that controls an exit of exhaust of gas that includes the combustion products at a requisite pressure to yield a thrust.

An acoustic compression engine that includes an air intake section adapted to intake a volume of air. The volume of air is mixed with fuel within the air intake section. The acoustic compression engine also includes a resonant chamber adapted to intake a volume of air mixed with fuel from the air intake section. Compression of the volume of air mixed with fuel occurs within the resonant chamber and compression of the volume of air and fuel mixture is based on combustion of compressed air and fuel mixture and a resonant cycle of the acoustic compression engine. The acoustic compression engine further includes at least one exhaust nozzle that controls an exit of exhaust of gas that includes the combustion products at a requisite pressure to yield a thrust.

A pressure gain combustor comprises a detonation chamber, a pre-combustion chamber, an oxidant swirl generator, an expansion-deflection (E-D) nozzle, and an ignition source. The detonation chamber has an upstream intake end and a downstream discharge end, and is configured to allow a supersonic combustion event to propagate therethrough. The pre-combustion chamber has a downstream end in fluid communication with the detonation chamber intake end, an upstream end in communication with a fuel delivery pathway, and a circumferential perimeter between the upstream and downstream ends with an annular opening in communication with an annular oxidant delivery pathway. The oxidant swirl generator is located in the oxidant delivery pathway and comprises vanes configured to cause oxidant flowing past the vanes to flow tangentially into the pre-combustion chamber thereby creating a high swirl velocity zone around the annular opening and a low swirl velocity zone in a central portion of the pre-combustion chamber. The E-D nozzle is positioned in between the pre-combustion chamber and detonation chamber and provides a diffusive fluid pathway therebetween. The ignition source is in communication with the low swirl velocity zone of the pre-combustion chamber. This configuration is expected to provide a combustor with a relatively low total run-up DDT distance and time, thereby enabling high operating frequencies and corresponding high combustor performance.

A pressure gain combustor comprises a detonation chamber, a pre-combustion chamber, an oxidant swirl generator, an expansion-deflection (E-D) nozzle, and an ignition source. The detonation chamber has an upstream intake end and a downstream discharge end, and is configured to allow a supersonic combustion event to propagate therethrough. The pre-combustion chamber has a downstream end in fluid communication with the detonation chamber intake end, an upstream end in communication with a fuel delivery pathway, and a circumferential perimeter between the upstream and downstream ends with an annular opening in communication with an annular oxidant delivery pathway. The oxidant swirl generator is located in the oxidant delivery pathway and comprises vanes configured to cause oxidant flowing past the vanes to flow tangentially into the pre-combustion chamber thereby creating a high swirl velocity zone around the annular opening and a low swirl velocity zone in a central portion of the pre-combustion chamber. The E-D nozzle is positioned in between the pre-combustion chamber and detonation chamber and provides a diffusive fluid pathway therebetween. The ignition source is in communication with the low swirl velocity zone of the pre-combustion chamber. This configuration is expected to provide a combustor with a relatively low total run-up DDT distance and time, thereby enabling high operating frequencies and corresponding high combustor performance.