222results about "Pulsating combustion" patented technology

A melter apparatus includes a floor, a ceiling, and a substantially vertical wall connecting the floor and ceiling at a perimeter of the floor and ceiling, a melting zone being defined by the floor, ceiling and wall, the melting zone having a feed inlet and a molten glass outlet positioned at opposing ends of the melting zone. The melting zone includes an expanding zone beginning at the inlet and extending to an intermediate location relative to the opposing ends, and a narrowing zone extending from the intermediate location to the outlet. One or more burners, at least some of which are positioned to direct combustion products into the melting zone under a level of molten glass in the zone, are also provided.

The present invention relates to an exhaust gas guide of a gas turbine, which is situated between the gas turbine and a downstream waste heat boiler or a downstream gas diverter and which comprises a flow channel which has a cross-section expanding in at least some areas in the main flow direction, having installed surfaces influencing the flow. In order to achieve a more compact implementation of the exhaust gas guide and simultaneously avoid or reduce pressure losses, the installed surfaces are implemented as a swirl device generating a leading edge swirl, which is situated in the diverging area of the flow channel and is implemented to distribute the exhaust gas flow uniformly over the flow cross-sectional area upon entry into the waste heat boiler or the gas diverter. Furthermore, the present invention relates to a method for mixing the exhaust gas of a gas turbine with hot exhaust gas streams generated in an auxiliary firing of at least one burner. This thorough mixing is achieved by generating at least one leading edge swirl system in the flow channel.

Processes of converting to feedstocks comprising hydrocarbons to compositions comprising light hydrocarbon products are described herein. Also described are processes and methods of producing and refining compositions comprising terpenes from biomass that can be suitable as a fuel product.

A pulsed detonation combustor (PDC) is described. The PDC includes an outer casing defining a first hollow chamber configured to receive a flow and an inner liner. The inner liner includes at least one portion positioned within the first hollow chamber and configured to receive the flow from a plenum formed between the outer casing and inner liner. The PDC further includes a flow turning device with geometric features configured to direct the flow from the plenum to a second hollow chamber defined within the inner liner. The PDC also includes at least one fuel injection port located downstream of an inlet to the outer casing and an ignition device located downstream of the at least one fuel injection port and configured to periodically ignite fuel.

Sequenced pulses of light from an excitation laser with at least two resonator cavities with separate output couplers are directed through a light modulator and a first polarzing analyzer. A portion of the light not rejected by the first polarizing analyzer is transported through a first optical fiber into a first ignitor laser rod in an ignitor laser. Another portion of the light is rejected by the first polarizing analyzer and directed through a halfwave plate into a second polarization analyzer. A first portion of the output of the second polarization analyzer passes through the second polarization analyzer to a second, oscillator, laser rod in the ignitor laser. A second portion of the output of the second polarization analyzer is redirected by the second polarization analyzer to a second optical fiber which delays the beam before the beam is combined with output of the first ignitor laser rod. Output of the second laser rod in the ignitor laser is directed into the first ignitor laser rod which was energized by light passing through the first polarizing analyzer. Combined output of the first ignitor laser rod and output of the second optical fiber is focused into a combustible fuel where the first short duration, high peak power pulse from the ignitor laser ignites the fuel and the second long duration, low peak power pulse directly from the excitation laser sustains the combustion.

A pulse detonation (PD) assembly includes at least one PD chamber having a wall, which defines cooling holes arranged along at least a portion of the PD chamber. A manifold extends around the PD chamber. The manifold and PD chamber are separated by a bypass region. A PD assembly with reverse flow cooling includes at least one PD chamber. A sleeve extends around the PD chamber. The sleeve and PD chamber are separated by a reverse flow cooling passage configured to receive a flow of air and to flow the air in a reverse direction to supply the PD chamber. A PD assembly with bypass flow cooling includes at least one PD chamber and a manifold extending around the PD chamber(s), which are separated by a bypass region. The PD assembly further includes a mixing plenum configured to receive and mix the bypass flow from the bypass region and the detonation by-products from the PD chamber(s).

A method and an apparatus for heat-treatment of materials, preferably metals, are provided. The method comprises the following steps: providing and maintaining a flame by supplying a burner with fuel and gas containing at least 80 percent by volume oxygen; creating an oxygen-hot exhaust mixture by recirculating exhausts from the flame to the gas containing oxygen by means of an ejector effect; mixing the oxygen-exhaust mixture and the fuel; and providing a secondary recirculation by recirculating exhausts from the flame to the oxygen-exhaust-fuel mixture. The method and apparatus allow for extremely low NOx emissions and high efficiency, resulting in an environmentally friendly and at the same time cost effective process.

In the apparatus of the invention, a first excitation laser or other excitation light source is used in tandem with an ignitor laser to provide a compact, durable, engine deployable fuel ignition laser system. Reliable fuel ignition is provided over a wide range of fuel conditions by using a single remote excitation light source for one or more small lasers located proximate to one or more fuel combustion zones.In the embodiment of the invention claimed herein, the beam from the excitation light source is split with a portion of it going to the ignitor laser and a second portion of it being combined with either the first portion after a delay before injection into the ignitor laser.

The periodic equivalence ratio modulation (PERM) method and apparatus significantly reduces and / or eliminates unstable conditions within a combustion chamber. The method involves modulating the equivalence ratio for the combustion device, such that the combustion device periodically operates outside of an identified unstable oscillation region. The equivalence ratio is modulated between preselected reference points, according to the shape of the oscillation region and operating parameters of the system. Preferably, the equivalence ratio is modulated from a first stable condition to a second stable condition, and, alternatively, the equivalence ratio is modulated from a stable condition to an unstable condition. The method is further applicable to multi-nozzle combustor designs, whereby individual nozzles are alternately modulated from stable to unstable conditions. Periodic equivalence ratio modulation (PERM) is accomplished by active control involving periodic, low frequency fuel modulation, whereby low frequency fuel pulses are injected into the main fuel delivery. Importantly, the fuel pulses are injected at a rate so as not to affect the desired time-average equivalence ratio for the combustion device.

A method of combustion stability control for a gas turbine engine is provided, and includes the steps of receiving by a stability controller, information regarding environmental and operating conditions, and comparing the environmental and operating conditions to pre-programmed information to determine if a likelihood of combustion instability exists. The method further includes the steps of determining optimal fuel modulation frequency and amplitude for the environmental condition to reduce combustion instability, if a likelihood of combustion instability exists, and actuating at least one fuel modulation valve to, at the optimal fuel modulation frequency and amplitude, reduce combustion instability, if a likelihood of combustion instability exists. Systems for modulating fuel flow are also provided.

Methods and systems are provided for inducing combustion dynamics within turbine engines to remove combustion deposits within the turbine engine during operation of the turbine engine.

A pulse detonation engine (10) is provided with an aerovalve (14) for controlling the pressure of injected propellants (Ox, Fuel) in an open-ended detonation chamber (26). The propellants are injected at such pressure and velocity, and in a direction generally toward a forward thrust wall end (16) of the detonation chamber (26), an aerovalve (14) is formed which effectively inhibits or prevents egress of the propellant from the detonation chamber (26). A shock wave (34) formed by the injected propellant acts, after reflection by the thrust wall end (16) and in combination with the aerovalve (14), to compress and conserve, or increase, the pressure of the injected propellant. Carefully timed ignition (28) effects a detonation pulse under desired conditions of maintained, or increased, pressure. Termination of the propellant injection serves to “open” the aerovalve (14), and exhaust of the combusted propellants occurs to produce thrust. Alternate embodiments of propellant injection mechanisms (12, 112) provide pulse valves (24, 122, 124) each having a fixed slotted disk (40, 140, 240) and a rotating slotted disk (42, 142, 242) to provide the desired high speed valving of discrete pulses of propellant for injection.

A pulse detonation (PD) assembly includes a number of PD chambers adapted to expel respective detonation product streams and a number of barriers disposed between respective pairs of PD chambers. The barriers define, at least in part, a number of sectors that contain at least one PD chamber. A hybrid engine includes a number of PD chambers and barriers. The hybrid engine further includes a turbine assembly having at least one turbine stage, being in flow communication with the PD chambers and being configured to be at least partially driven by the detonation product streams. A segmented hybrid engine includes a number of PD chambers and segments configured to receive and direct the detonation product streams from respective PD chambers. The segmented hybrid engine further includes a turbine assembly configured to be at least partially driven by the detonation product streams.

A constant volume combustor device includes detonative combustion. In one form the wave rotor of the constant volume combustor is supported by magnetic bearings.

A method and device for controllably combusting combustible material, including a combustion device comprising an elongate combustion tube having an inlet section including an inlet for combustible material, an ignition section, including an igniter displaced along a length of the tube from the inlet section to ignite the combustible material, and at least one energy extraction device operatively coupled to the combustion tube and configured to extract energy from combustion of the combustible mixture.

A pulse detonation engine comprises a primary air inlet; a primary air plenum located in fluid communication with the primary air inlet; a secondary air inlet; a secondary air plenum located in fluid communication with the secondary air inlet, wherein the secondary air plenum is substantially isolated from the primary air plenum; a pulse detonation combustor comprising a pulse detonation chamber, wherein the pulse detonation chamber is located downstream of and in fluid communication with the primary air plenum; a coaxial liner surrounding the pulse detonation combustor defining a cooling plenum, wherein the cooling plenum is in fluid communication with the secondary air plenum; an axial turbine assembly located downstream of and in fluid communication with the pulse detonation combustor and the cooling plenum; and a housing encasing the primary air plenum, the secondary air plenum, the pulse detonation combustor, the coaxial liner, and the axial turbine assembly.

Pressure and density of a gaseous mixture are increased in the process of introducing the gaseous mixture into the combustor of an air-breathing pulse detonation engine employing atmospheric oxygen as an oxidizer. The exit valve 20 able to be opened and closed is provided at the outlet of the combustor 15, an air cooler 12 is provided in the exit of the intake, and density is increased by exchange of heat of the air received at the intake with a coolant in the air cooler 12. Furthermore, by closing the exit valve 20 provided in the outlet of the combustor during the process of loading the gaseous mixture, transition to the detonation process is possible without expansion of the high-pressure high density air obtained by ram-compression at the intake.

A constant volume combustor device includes, in one form, a detonative combustion. In one form the wave rotor of the constant volume combustor is supported by magnetic bearings. The constant volume combustor device includes a rotor having a number of fluid passageways that rotate about an axis. End plates having at least one inlet port and at least one outlet port are located on either end of the rotor. Relatively compressed air enters the rotor through the at least one inlet port, is burned with fuel in a pulsed combustion process, and exits at least one exit port. The pulsed combustion process can be a pulsed detonation combustion process or a pulsed deflagration combustion process.

An engine contains a compressor stage, a pulse detonation combustion stage and a turbine stage. The pulse detonation combustion stage contains at least one pulse detonation combustor which has an inlet portion. The pulse detonation combustor is oriented longitudinally and / or tangentially with respect to a centerline of the engine.

Pulse detonation combustors of valveless construction. One valveless pulse detonation combustor, having a tube with a closed end and an open end, is constructed with a flame accelerator within the tube, adjacent the open end. A valveless, apertured flow restrictor is positioned between the flame accelerator and the closed end of the tube. A sparking device is positioned within the tube, between the flow restrictor and the flame accelerator. Valveless fuel and air ports are positioned between the flow restrictor and the closed end of the tube. Substantially right-angle manifold passageways are in communication with each of the ports.

A pulse detonation combustor includes at least one plenum located along the length of the pulse detonation combustor. The plenum can be located: 1) proximate an air valve; 2) between a fuel injection port and an ignition source; 3) downstream of both the fuel injection port and the ignition source; and 4) proximate an exit nozzle of the pulse detonation combustor. In addition, the pulse detonation combustor can have multiple plenums, for example, proximate the air valve and proximate the exit nozzle. The location and dimensions of the plenum can be selectively adjusted to control mechanical loading on the wall, the velocity of fluid flowing within the combustor, and the pressure generated by the pulse detonation combustor.

A method and a device for combusting gaseous fuel which contains hydrogen or consists of hydrogen, includes a burner which provides a swirl generator (1) into which liquid fuel is feedable centrally along a burner axis (A), forming a liquid fuel column which is conically formed and which is enveloped by, and mixed through with, a rotating combustion air flow which flows tangentially into the swirl generator (1). The gaseous fuel is fed inside the swirl generator (1) largely axially and / or coaxially to the burner axis (A), forming a fuel flow with a largely spatially defined flow pattern (9) which is maintained inside the burner and bursts open in the region of the burner outlet.

The invention relates to heat exchanger tubes acting like resonant tubes of a Helmholtz resonator and used as swirl tubes. They are capable of drastically increasing heat transfer in the boundary layers determining the heat flow to be exchanged as a result of their geometrically deformed surfaces.