149 results about "Fuel spray" patented technology

An aircraft gas turbine engine includes a combustor, with a combustion chamber and fuel spray nozzles to inject fuel into the chamber. The nozzles include first and second subsets. The first subset of nozzles is supplied with fuel at a greater rate than each of the second subset. A ratio of nozzles in the first subset to the second subset is 1:3 to 1:6. A lean cruise nvPM emissions index ratio isEIcruise⁡(lean),SAFEIcruise⁡(lean),FF,where EIcruise(lean),SAF isEImaxTO,SAF+EIclimb,SAF2and EIcruise(lean),FF isEImaxTO,FF+EIclimb,FF2.EImaxTO,SAF is nvPM emissions index operating at 100% available thrust and EIclimb,SAF is the nvPM emissions index operating at 85% available thrust if fuel includes sustainable aviation fuel. EImaxTO,FF is the nvPM emissions index operating at 100% available thrust and EIclimb,FF is the nvPM emissions index at 85% available thrust if fuel is a fossil-based hydrocarbon. The lean cruise nvPM emissions index ratio is less than 1.

A gas turbine engine for an aircraft is disclosed. The gas turbine engine comprises: a combustor, comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustor is operable in a condition in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein a ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:2 to 1:5. A thrust nvPM emissions index ratio is defined as:EImaxTO / FmaxTOEIidle / Fidlewhere: EIidle is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine if operating at around 7% available thrust for given operating conditions; EImaxTO is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine if operating at around 100% available thrust for the given operating conditions; FmaxTO is the thrust of the gas turbine engine at around 100% available thrust in kN for the given operating conditions; and Fidle is the thrust of the gas turbine engine at around 7% available thrust in kN for the given operating conditions. The thrust nvPM emissions index ratio is greater than 0.001. The gas turbine engine is configured to provide fuel comprising a sustainable aviation fuel (SAF) to the plurality of fuel spray nozzles. Also disclosed is a method of operating the gas turbine engine.

A gas turbine engine for an aircraft is disclosed. The gas turbine engine comprises: a combustor, comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustor is operable in a condition in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein a ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6. A MTO nvPM emissions index ratio is defined as:EImaxTO,SAFEImaxTO,FFwhere: EImaxTO,SAF is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for given operating conditions if a fuel provided to the plurality of fuel spray nozzles comprises a sustainable aviation fuel (SAF); and EImaxTO,FF is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for the given operating conditions if a fuel provided to the plurality of fuel spray nozzles is a fossil-based hydrocarbon fuel. The MTO nvPM emissions index ratio of the gas turbine engine is less than 1. The gas turbine engine is configured to provide fuel comprising a SAF to the plurality of fuel spray nozzles. Also disclosed are methods of operating the gas turbine engine.

A gas turbine engine for an aircraft. The gas turbine engine comprising: a combustor, comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustor is operable in a condition in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein a ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:2 to 1:5. An MTO nvPM emissions index ratio-modified fuel flow is defined as:EImaxTO,SAFEImaxTO,FF×Wf,maxTOwhere: EImaxTO,SAF is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for given operating conditions if a fuel provided to the plurality of fuel spray nozzles comprises a sustainable aviation fuel (SAF); EImaxTO,FF is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for the given operating conditions if a fuel provided to the plurality of fuel spray nozzles is a fossil-based hydrocarbon fuel; and Wf,maxTO is the mass flow rate of fuel provided to the plurality of fuel spray nozzles in kg / s when the gas turbine engine is operating at around 100% available thrust for the given operating conditions. The MTO nvPM emissions index ratio-modified fuel flow of the gas turbine engine in kg / s is less than 2. The gas turbine engine is configured to provide fuel comprising a SAF to the plurality of fuel spray nozzles. Also disclosed is a method of operating the gas turbine engine.

A gas turbine engine includes a combustor with a combustion chamber and fuel spray nozzles to inject fuel into the combustion chamber. The nozzles include a first and second subset. Each of the nozzles of the first subset is supplied with fuel at a greater rate than each of the second subset. A ratio of nozzles in the first subset to nozzles in the second subset from 1:3 to 1:6. A fuel-flow nvPM emissions index ratio isEIidle×Wf,idleRImaxTO×Wf,maxTO.EIidle and EImaxTO are the system loss corrected nvPM emissions index in mg / kg operating at around 7% and 100% available thrust for the given operating conditions, respectively. Wf,idle and Wf,maxTO are the rate of fuel flow to the fuel spray nozzles in kg / s at around 7% and 100% available thrust for the given operating conditions, respectively. The fuel-flow nvPM emissions index ratio of the gas turbine engine is less than 0.3.

A gas turbine engine includes: a rich burn, quick quench, lean burn combustor having a number of fuel spray nozzles in the range 14-22 or a number of fuel spray nozzles per unit engine core size in the range 2 to 6. An nvPM emissions index ratio is defined as:EIidle×Wf,idleEImaxTO×Wf,maxTOwhere: EIidle and EImaxTO are respectively the nvPM emissions index in mg / kg of gas turbine engine if operating at around 7% or 100% available thrust for given operating conditions; Wf,idle and Wf,maxTO are respectively the rate of fuel flow to fuel spray nozzles in kg / s at around 7% or 100% available thrust for given operating conditions. The fuel-flow nvPM emissions index ratio is less than 0.08. The gas turbine engine is configured to provide fuel including sustainable aviation fuel to fuel spray nozzles. Also disclosed is a method of operating the gas turbine engine.

A gas turbine engine for an aircraft. The gas turbine engine comprising: a rich burn, quick quench, lean burn (RQL) combustor having a number of fuel spray nozzles in the range of 14-22 or a number of fuel spray nozzles per unit engine core size in the range 2 to 6. An MTO nvPM emissions index ratio is defined as:EImaxTO,SAFEImaxTO,FFwhere: EImaxTO,SAF is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for given operating conditions if a fuel provided to the fuel spray nozzles comprises a sustainable aviation fuel (SAF); and EImaxTO,FF is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for the given operating conditions if a fuel provided to the fuel spray nozzles is a fossil-based hydrocarbon fuel. The MTO nvPM emissions index ratio of the gas turbine engine is less than 1. The gas turbine engine is configured to provide fuel comprising a SAF to the fuel spray nozzles. Also disclosed is a method of operating a gas turbine engine.

A gas turbine engine for an aircraft is disclosed. The gas turbine engine comprises: a combustor, comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustor is operable in a condition in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein a ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6. A MTO nvPM emissions index ratio is defined as:EImaxTO,SAFEImaxTO,FFwhere: EImaxTO,SAF is the nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for given operating conditions if a fuel provided to the plurality of fuel spray nozzles comprises a sustainable aviation fuel (SAF); and EImaxTO,FF is the nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for the given operating conditions if a fuel provided to the plurality of fuel spray nozzles is a fossil-based hydrocarbon fuel. The MTO nvPM emissions index ratio of the gas turbine engine is less than 1. The gas turbine engine is configured to provide fuel comprising a SAF to the plurality of fuel spray nozzles. Also disclosed are methods of operating the gas turbine engine.

A gas turbine engine includes: a rich burn, quick quench, lean burn combustor having a number of fuel spray nozzles in range of 14-22 or a number of fuel spray nozzles per unit engine core size in range 2 to 6. An MTO nvPM emissions index ratio is:EImaxTO,SAFEImaxTO,FF×Wf,maxTOwhere: EImaxTO,SAF and EImaxTO,FF are respectively the nvPM emissions index in mg / kg when operating around 100% available thrust for given operating conditions if fuel provided to fuel spray nozzles includes either sustainable aviation fuel (SAF) or fossil-based hydrocarbon fuel; Wf,maxTO is mass flow rate of fuel provided to fuel spray nozzles in kg / s when gas turbine engine is operating at around 100% available thrust for given operating conditions. MTO nvPM emissions index is less than 2. The gas turbine engine is configured to provide fuel including SAF to fuel spray nozzles. Also disclosed is method of operating gas turbine engine.

A gas turbine engine for an aircraft includes a combustor with a combustion chamber and fuel spray nozzles to inject fuel into the chamber. The nozzles include a first and second subset. The combustor is operable so each of the first subset is supplied with fuel at a greater rate than each of the second subset. A ratio of nozzles in the first subset to nozzles in the second subset is 1:3 to 1:6. A thrust nvPM emissions index ratio is EImaxTO / FmaxTO / EIidle / Fidle. EIidle is system loss corrected nvPM emissions index in mg / kg of the engine operating at around 7% available thrust. EImaxTO is system loss corrected nvPM emissions index in mg / kg of the engine at around 100% available thrust. FmaxTO is thrust of the engine at around 100% available thrust. Fidle is thrust at around 7% available thrust. The thrust nvPM emissions index ratio is between 0.0009 and 0.02.

A gas turbine engine for an aircraft includes a combustor with a combustion chamber and fuel spray nozzles to inject fuel into the chamber. The nozzles include a first and second subset. The combustor is operable so each of the first subset is supplied with fuel at a greater rate than each of the second subset. A ratio of nozzles in the first subset to the second subset is 1:3 to 1:6. A fuel-flow nvPM emissions index ratio isEIidle × Wf,idleEImaxTO × Wf,maxTO.EIidle is the system loss corrected nvPM emissions index in mg / kg of the engine at around 7% available thrust. EImaxTO is the index at around 100% available thrust. Wf,idle is the rate of fuel to the nozzles in kg / s at around 7% available thrust. Wf,maxTO is the rate of fuel to the nozzles in kg / s at around 100% available thrust. The index ratio is between 0.357 and 8.

A gas turbine engine for an aircraft. The gas turbine engine comprising: a rich burn, quick quench, lean burn (RQL) combustor having a number of fuel spray nozzles in the range of 14-22 or a number of fuel spray nozzles per unit engine core size in the range 2 to 6. A first idle-MTO nvPM emissions index ratio is defined as:EIidle / EImaxTO where: EIidle is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine if operating at around 7% available thrust for given operating conditions; and EImaxTO is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine if operating at around 100% available thrust for the given operating conditions. The first idle-MTO nvPM emissions index ratio of the gas turbine engine is less than 0.8. The gas turbine engine is configured to provide fuel comprising a sustainable aviation fuel (SAF) to the fuel spray nozzles. A method of operating the gas turbine engine is also disclosed.

A gas turbine engine has a first subset of fuel spray nozzles and a second subset of fuel spray nozzles. A combustor is operable with the first subset of fuel spray nozzles supplied with fuel at a greater fuel flow rate than each the second subset of fuel spray nozzles. A a ratio of the first subset of fuel spray nozzles to the second subset of fuel spray nozzles is 1:2 to 1:5. A first idle-MTO nvPM emissions index ratio is:EIidleEImaxTOwhere: EIidle is the system loss corrected nvPM emissions index in mg / kg operating at around 7% available thrust; and EImaxTO is the system loss corrected nvPM emissions index in mg / kg operating at around 100% available thrust; and the first idle-MTO nvPM emissions index ratio of the gas turbine engine is less than 60. A sustainable aviation fuel (SAF) can be provided to the fuel spray nozzles.

A gas turbine engine has a first subset of fuel spray nozzles and a second subset of fuel spray nozzles. A combustor is operable with the first subset of fuel spray nozzles supplied with fuel at a greater flow rate than each of the second subset of fuel spray nozzles. A ratio of the first subset of fuel spray nozzles to the second subset of fuel spray nozzles is 1:2 to 1:5. A first idle-MTO nvPM emissions index ratio is:EIidleEImaxTO,where: Elidle is the nvPM emissions index in mg / kg operating at around 7% available thrust; ElmaxTO is the nvPM emissions index in mg / kg of the gas turbine engine operating at around 100% available thrust; and the first idle-MTO nvPM emissions index ratio of the gas turbine engine is less than 60. A sustainable aviation fuel (SAF) can be provided to the fuel spray nozzles.

Disclosed are an apparatus for a simulation test of diesel engine fuel spray in an alpine environment and a test method, the apparatus comprising a fuel storage and pretreatment device, a fuel injection system, an optical visualization system, an environment chamber, and a spray pretreatment system. In alpine environmental conditions, the apparatus can achieve high-pressure injection of liquid, separate injected atomized mist into fine droplets and impinge same on a wall surface by means of a multi-droplet generation apparatus and a wall surface apparatus, and observe and record the whole process by means of an optical visualization path. According to the present invention, the problem of difficulty in distinguishing droplets due to the coalescence of spray into a sheet is avoided, the costs of a traditional spray and droplet test solution can be significantly reduced, and the problem of a high level of dependence on a control program in a constant volume vessel solution is solved. According to the present invention, simulation of spray test in an alpine environment is possible, and the test apparatus has a simple structure. Moreover, it is possible to conduct regular research on free spray, multi-droplet wall impingement, spray wall impingement, and development characteristics thereof under conditions such as different altitudes and different temperatures.

The invention discloses a (NiCr-Cr3C2) / NiCr composite coating and a preparation method thereof, and belongs to the technical field of composite material preparation.The preparation method of the (NiCr-Cr3C2) / NiCr composite coating comprises the following steps that an HVOF technology (high-speed oxygen fuel spraying technology) is adopted, NiCr powder and NiCr-Cr3C2 powder are sequentially sprayed on the surface of a base material, and a NiCr transition layer and a NiCr-Cr3C2 working layer are formed respectively; and then annealing treatment is carried out, and the (NiCr-Cr3C2) / NiCr composite coating is obtained. Through the annealing treatment, especially the annealing at 700 DEG C, a nanoscale secondary carbide and polycrystalline ring net structure can be formed, so that the coating obtains the optimal comprehensive performance, namely the highest coating section microhardness (1242HV0.2), the optimal toughness (7.9 MPa.m < 1 / 2 >) and the lowest wear rate (0.37 * 10 <-5 > mm < 3 > / N.m).

A gas turbine engine for aircraft includes a combustor with a combustion chamber and fuel spray nozzles to inject fuel into the combustion chamber. The fuel spray nozzles include a first subset and a second subset of nozzles. Each of the first subset is supplied with fuel at a greater rate than each of the second subset. A ratio of the first subset to the second subset is 1:2 to 1:5. A MTO nvPM emissions index ratio isEImaxTO,SAFEImaxTO,FF.EImaxTO,SAF is nvPM emissions index in mg / kg of the engine when operating at around 100% available thrust if fuel provided to the fuel spray nozzles includes sustainable aviation fuel. EImaxTO,FF IS nvPM emissions index in mg / kg of the engine when operating at around 100% available thrust if fuel provided to the fuel spray nozzles is fossil-based hydrocarbon fuel. The MTO nvPM emissions index ratio is less than 1.

The invention discloses a combustion chamber fuel injection and oil-gas mixing system suitable for a low-temperature environment, and belongs to the field of combustion chambers of gas turbines, the combustion chamber fuel injection and oil-gas mixing system comprises a flame tube, a centrifugal nozzle and a two-stage cyclone which are coaxially arranged, after fuel is atomized through the centrifugal nozzle and enters, the fuel is further atomized through rotational flow of an inner ring of the two-stage cyclone and enters the flame tube, and the fuel is injected into the combustion chamber through the centrifugal nozzle. External high-pressure air is swirled through the outer ring of the two-stage swirler to form swirling air, and internal fuel spray is crushed, atomized and mixed; a venturi tube is arranged at the end, close to the flame tube, of the inner ring of the two-stage cyclone, vortex generators are evenly arranged on the inner wall of the expansion section of the venturi tube in the circumferential direction, and oil mist with the small and even particle size is formed after the atomized mist is acted. Through multi-stage rotational flow, oil mist with fine and uniform granularity is formed, the atomization effect is optimized, and the fuel oil atomization quality and combustion stability in a low-temperature environment are improved.

A gas turbine engine for an aircraft is disclosed. The gas turbine engine comprises:a combustor, comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustor is operable in a condition in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein a ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6. A fuel-flow nvPM emissions index ratio is defined as:E⁢Iidle×Wf,idleE⁢ImaxTO×Wf,maxTOwhere: EIidle is the nvPM emissions index in mg / kg of the gas turbine engine if operating at around 7% available thrust for given operating conditions; EImaxTO is the nvPM emissions index in mg / kg of the gas turbine engine if operating at around 100% available thrust for the given operating conditions; Wf,idle is the rate of fuel flow to the fuel spray nozzles in kg / s at around 7% available thrust for the given operating conditions; and Wf,maxTO is the rate of fuel flow to the fuel spray nozzles in kg / s at around 100% available thrust for the given operating conditions. The fuel-flow nvPM emissions index ratio of the gas turbine engine is less than 0.3. The gas turbine engine is configured to provide fuel comprising a sustainable aviation fuel (SAF) to the plurality of fuel spray nozzles. Also disclosed are methods of operating a gas turbine engine.

This invention discloses a high-disturbance spray boom structure based on plasma-excited coupled aerodynamically assisted atomization, relating to the field of afterburner technology for aero-engines. It includes: a shell with an air inlet; a fuel pipe with a fuel delivery channel; the fuel pipe extending into the shell and forming an air channel with it; a first insulating platform with a collision atomization zone and an atomization development zone; the first insulating platform is connected to the output end of the fuel pipe, and its neck has several fuel-gas atomization channels; a second insulating platform with a plasma discharge region; the second insulating platform is snapped into the first insulating platform; a high-voltage electrode located between the first and second insulating platforms; and a grounding electrode located between the second insulating platform and the shell. This invention employs the coupling of plasma excitation with aerodynamically assisted atomization and cross-collision to perform three consecutive actions on the fuel spray, thereby improving the fuel atomization performance of the high-disturbance spray boom.

A gas turbine engine for an aircraft. The gas turbine engine comprising: a rich burn, quick quench, lean burn (RQL) combustor having a number of fuel spray nozzles in the range 14-22 or a number of fuel spray nozzles per unit engine core size in the range 2 to 6. A fuel-flow nvPM emissions index ratio is defined as:EIidle×Wf,idleEImax⁢TO×Wf,maxTOwhere: EIidle is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine if operating at around 7% available thrust for given operating conditions; and EImaxTO is the system loss corrected nvPM emissions index in mg / kg of the gas turbine engine if operating at around 100% available thrust for the given operating conditions; Wf,idle is the rate of fuel flow to the fuel spray nozzles in kg / s at around 7% available thrust for the given operating conditions; and Wf,maxTO is the rate of fuel flow to the fuel spray nozzles in kg / s at around 100% available thrust for the given operating conditions. The fuel-flow nvPM emissions index ratio of the gas turbine engine is less than 0.08. The gas turbine engine is configured to provide fuel comprising a sustainable aviation fuel (SAF) to the fuel spray nozzles. Also disclosed is a method of operating the gas turbine engine.

The embodiment of the invention provides a preparation method of an anti-erosion gradient coating. The preparation method comprises the steps that a to-be-repaired area on the surface of a workpiece is subjected to cleaning and sand blasting treatment; the first powder, the second powder and the third powder are sequentially sprayed to the to-be-repaired area through the high velocity oxy-fuel spraying technology, and the gradient coating is prepared; the first powder, the second powder and the third powder all comprise hard alloy powder and base material powder made of the same material as the workpiece, the content of the hard alloy powder in the first powder is smaller than that of the hard alloy powder in the second powder, and the content of the hard alloy powder in the second powder is smaller than that of the hard alloy powder in the third powder; and after the workpiece is sprayed and naturally cooled, the surface of the sprayed workpiece is subjected to protection treatment. According to the method, the anti-erosion coating (gradient coating) can be prepared on the basis of hypersonic flame spraying. And under the action of the gradient coating, a compact coating with smaller tensile stress can be obtained, and the properties of erosion resistance, water erosion resistance and the like of the workpiece are improved.

A gas turbine engine has a first subset of fuel spray nozzles and a second subset of fuel spray nozzles. A combustor is operable with the first subset of fuel spray nozzles supplied with fuel at a greater flow rate than each of the second subset of fuel spray nozzles. A ratio of the first subset of fuel spray nozzles to the second subset of fuel spray nozzles is 1:2 to 1:5. A first idle-MTO nvPM emissions index ratio is:EIidleEImax⁢TO,where: EIidle is the nvPM emissions index in mg / kg operating at around 7% available thrust; EImaxTO is the nvPM emissions index in mg / kg of the gas turbine engine operating at around 100% available thrust; and the first idle-MTO nvPM emissions index ratio of the gas turbine engine is less than 60. A sustainable aviation fuel (SAF) can be provided to the fuel spray nozzles.

A gas turbine engine has a first subset of fuel spray nozzles and a second subset of fuel spray nozzles. A combustor is operable with the first subset of fuel spray nozzles supplied with fuel at a greater fuel flow rate than each the second subset of fuel spray nozzles. A a ratio of the first subset of fuel spray nozzles to the second subset of fuel spray nozzles is 1:2 to 1:5. A first idle-MTO nvPM emissions index ratio is:EIidleEImaxTOwhere: EIidle is the system loss corrected nvPM emissions index in mg / kg operating at around 7% available thrust; and EImaxTO is the system loss corrected nvPM emissions index in mg / kg operating at around 100% available thrust; and the first idle-MTO nvPM emissions index ratio of the gas turbine engine is less than 60. A sustainable aviation fuel (SAF) can be provided to the fuel spray nozzles.

A gas turbine engine for an aircraft includes a rich burn, quick quench, lean burn (RQL) combustor having 14-22 fuel spray nozzles or a number of fuel spray nozzles per unit engine core size in the range 2 to 6. A first idle-MTO nvPM emissions index ratioEIidleEImaxTO.EIidle is the nvPM emissions index in mg / kg of the gas turbine engine if operating at around 7% available thrust for given operating conditions. EImaxTO is the nvPM emissions index in mg / kg of the gas turbine engine if operating at around 100% available thrust for the given operating conditions. The first idle-MTO nvPM emissions index ratio of the gas turbine engine is less than 0.8. The gas turbine engine is configured to provide fuel comprising a sustainable aviation fuel (SAF) to the fuel spray nozzles.

The invention discloses a burner nozzle structure capable of improving the fuel distribution characteristic. A bluff body swirl vane comprises a plurality of swirl single pieces, a swirl channel is formed between every two adjacent swirl single pieces, the swirl single pieces form an incident flow face on the incident flow side, and when fluid impacts the incident flow face, streaming is formed, wide wake flow is generated, and the phenomenon that the fluid falls off along with vortexes is achieved; and the fuel supply system comprises a fuel cavity and a fuel pipe, one end of the fuel cavity is connected with the fuel pipe, the fuel pipe is arranged along the central axis of the combustor shell, and the fuel cavity is provided with a fuel spray hole communicated into the rotational flow channel. The design of the trapezoidal cross section and the incident flow surface of each rotational flow single piece is utilized to enable fluid to form streaming, wake flow and vortex shedding, turbulent mixing and high-temperature flue gas backflow are enhanced, meanwhile, accurate fuel distribution is achieved through the fuel cavities, the fuel pipes and the fuel spray holes in one-to-one correspondence with the rotational flow channels, combustion-supporting air distribution is further optimized through the multi-stage radial flow dividing rings in the rotational flow channels, and the combustion-supporting effect is improved. And the mixing uniformity of the fuel and the combustion-supporting air is effectively improved.

A gas turbine engine for an aircraft is disclosed. The gas turbine engine comprises: a combustor, comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustor is operable in a condition in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein a ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:2 to 1:5. A thrust nvPM emissions index ratio is defined as:EImaxTO / FmaxTOEIidle / Fidlewhere: EIidle is the nvPM emissions index in mg / kg of the gas turbine engine if operating at around 7% available thrust for given operating conditions; EImaxTO is the nvPM emissions index in mg / kg of the gas turbine engine if operating at around 100% available thrust for the given operating conditions; FmaxTO is the thrust of the gas turbine engine at around 100% available thrust in kN for the given operating conditions; and Fidle is the thrust of the gas turbine engine at around 7% available thrust in kN for the given operating conditions. The thrust nvPM emissions index ratio is greater than 0.001. The gas turbine engine is configured to provide fuel comprising a sustainable aviation fuel (SAF) to the plurality of fuel spray nozzles. Also disclosed is a method of operating the gas turbine engine.

The invention relates to the technical field of corrosion-resistant high-temperature sintering kiln furniture, and discloses a gradient composite corrosion-resistant kiln furniture for sintering electronic components and a preparation method thereof, the gradient composite corrosion-resistant kiln furniture comprises a gradient composite matrix, a laser microtexturing layer, an interface strengthening transition layer and a double-layer composite coating, the double-layer composite coating is formed by a rare earth oxide and non-metallic element powder through a high-temperature in-situ reaction, the double-layer composite coating is composed of a porous buffer layer and a compact anti-corrosion layer, and the compact anti-corrosion layer is obtained through a high-speed oxygen fuel spraying and amorphous precursor dipping secondary curing process. The interface strengthening transition layer is introduced into the gradient matrix, the interface strengthening transition layer is formed by the rare earth oxide and the non-metallic element powder through the high-temperature in-situ reaction, a compound phase with chemical inertness and self-healing capacity is constructed, permeation of a corrosion medium into the matrix is effectively blocked, and a compact anti-corrosion layer in the double-layer composite coating has a good anti-corrosion effect. Extremely densification of the coating is completed through high-speed oxygen fuel spraying and amorphous precursor dipping secondary curing.

The invention discloses a multifunctional catalyst for a diesel vehicle and a preparation method, and relates to the field of catalyst preparation, the multifunctional catalyst for the diesel vehicle comprises a precious metal coating and an SCR coating which are arranged in a layered mode, and the SCR coating is located above the precious metal coating; the SCR coating is of a sectional structure and comprises an SCR coating front section and an SCR coating rear section. The problems that an existing catalyst is low in NOx efficiency during cold start, coating regeneration after HC / SO2 poisoning cannot be achieved at the same time, low N2O selectivity cannot be ensured, and unreacted NH3 cannot be treated at the same time are solved, by means of the layered and sectional type coating structure design, diesel oil or other hydrocarbon fuel sprayed backwards by a system can be rapidly oxidized through the bottom layer precious metal coating, reaction heat is generated, and the catalyst can be recycled. The temperature of the whole catalyst is increased, adsorbed HC and sulfide are oxidized and removed, and the SCR activity is recovered. And unreacted NH3 can be treated, so that the arrangement space of a post-treatment catalyst is saved. The upper-layer sectional type coating structure not only can efficiently convert NOx at a low temperature, but also can keep relatively low N2O selectivity.

A gas turbine engine for an aircraft is disclosed. The gas turbine engine comprises: a combustor, comprising a combustion chamber and a plurality of fuel spray nozzles configured to inject fuel into the combustion chamber, wherein the plurality of fuel spray nozzles comprises a first subset of fuel spray nozzles and a second subset of fuel spray nozzles, wherein the combustor is operable in a condition in which each of the fuel spray nozzles of the first subset of fuel spray nozzles is supplied with fuel at a greater fuel flow rate than each of the fuel spray nozzles of the second subset of fuel spray nozzles, wherein a ratio of the number of fuel spray nozzles in the first subset of fuel spray nozzles to the number of fuel spray nozzles in the second subset of fuel spray nozzles is in the range of 1:3 to 1:6. A MTO nvPM emissions index ratio is defined as:EImaxTO,SAFEImaxTO,FFwhere: EImaxTO,SAF is the nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for given operating conditions if a fuel provided to the plurality of fuel spray nozzles comprises a sustainable aviation fuel (SAF); and EImaxTO,FF is the nvPM emissions index in mg / kg of the gas turbine engine when operating at around 100% available thrust for the given operating conditions if a fuel provided to the plurality of fuel spray nozzles is a fossil-based hydrocarbon fuel. The MTO nvPM emissions index ratio of the gas turbine engine is less than 1. The gas turbine engine is configured to provide fuel comprising a SAF to the plurality of fuel spray nozzles. Also disclosed are methods of operating the gas turbine engine.