35results about How to "Shorter ignition delay time" patented technology

The invention discloses a method for coating micro/nano-metal powder by chemical vapor deposition, including: decomposing difluorocarbene precursor gas via a cracking pipe to generate difluorocarbene free radicals; contacting the generated difluorocarbene free radicals with micro/nano-metal powder, and due to polymerization between difluorocarbene free radicals, a compact polytetrafluoroethylene coating film is generated on the surface of micro/nano-metal powder. In allusion to disadvantages and defects of the application of micro/nano-metal powder in energy-containing materials, polytetrafluoroethylene is polymerized on the surface of metal powder by chemical vapor deposition in order to coat micro/nano-metal powder. In the invention, the ignition temperature of metal powder is effectively decreased, the ignition delay time is shortened, and the combustion speed of metal powder is improved; the surface of metal powder coated with polytetrafluoroethylene is highly hydrophobic, so that reactive metal powder can be effectively prevented from absorption of moisture and oxidation.

Cetane improvers based on triglycerides and petroleum fractions are disclosed that are at least one half as effective as commercially sold cetane improvers. In each case, the cetane improvers are nitrates produced through the nitration of medium to long chain compounds containing a double bond. Applications include use with diesel and alcohol fuels intended for use in diesel engines. The nitrates have advantages due to their good performance relative to their nitrogen content. Observed properties of some products indicate they also have lubricity and/or detergency enhancing capabilities when used with diesel fuel.

The invention discloses a sliding arc ignition device. The sliding arc ignition device comprises a contract-expansion type Laval nozzle, an outer shell, an air flow baffle, an electrode installation seat, a high-voltage anode and a locknut, wherein the contract-expansion type Laval nozzle and the electrode installation seat are fixed to the outer shell through threads, a hole is formed in a radial position of the outer shell, an air inlet connector is installed in the hole, the air flow baffle is clamped between the outer shell and the electrode installation seat, and the high-voltage anode is inserted into a central hole of the electrode installation seat, is stuck through sealants, is fixed through the locknut and is locked on the electrode installation seat. The sliding arc ignition device adopts an independent fuel inlet, the fuel supply can be increased after ignition succeeds, the fuel is catalyzed in a plasma region, and the functions of shortening ignition delay time and intensifying combustion are achieved. According to the design concept, a shell body serves as the installation base, machining difficulty is lowered, and when air flow baffles with different purposes are used, the air flow baffles can be placed in the outer shell without constraints, and assembling efficiency is improved.

The invention discloses an aluminum powder surface self-activation method. The method includes steps: adding aluminum powder into an anhydrous solvent, mixing, and stirring to disperse uniformly to form aluminum powder dispersion liquid; dissolving organic fluoride into a solvent to form organic fluorine solution, adding the organic fluorine solution into the aluminum powder dispersion liquid by acertain rate, and stirring to volatilize the solvent in which the organic fluoride is dissolved at a certain temperature, so that organic fluoride is slowly separated out by crystallization on the aluminum powder surface to form a compact surface activation layer; centrifugally separating to remove the solvent, washing, and performing vacuum drying at 60 DEG C to obtain organic fluorine surface self-activated aluminum powder. By forming of the organic fluorine self-activation layer on the aluminum powder surface, the aluminum powder ignition temperature can be effectively lowered while ignition delay time is shortened, combustion efficiency of aluminum powder in oxidants is improved while the energy releasing rate is increased, and the organic fluorine surface activation layer is effective in aluminum powder oxidation, so that stability is improved.

In a combustion unit, a fuel collision member is disposed between a fuel injection valve and a combustion chamber. The fuel collision member is positioned so that, a part of fuel injected from said fuel injection valve is introduced into the combustion chamber while colliding with the fuel collision member, and the other part of fuel is directly introduced into the combustion chamber without colliding with the fuel collision member. Thus, fuel introduced into the combustion chamber is atomized while being introduced into the combustion chamber in a wide range.

Provided is a filamentous arc plasma exciter based on swirl holes. An inner layer plasma swirler and an outer layer swirler are of a split type structure. The plurality of swirl holes are evenly distributed in a shell body of the inner layer plasma swirler. Two to five electrodes are disposed in the swirl holes through electrode installing bases correspondingly and divide the circumference of theshell body of the inner layer plasma swirler into n equal-length arc sections. The outer layer swirler is disposed on the upper end face of the inner layer plasma swirler. The filamentous arc discharge as one type of plasma discharge has huge advantages in the aspect of ignition and combustion supporting of a combustion chamber of an aero-engine, and the plasma exciter is combined with the head portion of the combustion chamber, so that ignition and combustion supporting can be integrated, and meanwhile active particles generated by plasma discharge are easily mixed with fuel oil molecules. The filamentous arc plasma exciter overcomes the defect that sliding arc plasmas cannot realize discharging when an inlet air flow rate is 0, improves combustion efficiency, is simple in structure and does not need to be equipped with a special air supply system or a special oil supply system.

The invention provides a palladium-ruthenium/aluminum-magnesium composite metal wire and a preparation method thereof. The composite metal wire takes a palladium-ruthenium alloy as a clad material and takes an aluminum-magnesium alloy as an inner core material. A preparation process comprises the following steps of: I, smelting the palladium-ruthenium alloy, and performing ingot casting to obtain a pipe blank; II, smelting the aluminum-magnesium alloy, and performing ingot casting to obtain a bar material; III, performing cold rolling and cold drawing on the pipe blank to obtain a palladium-ruthenium alloy pipe; IV, preparing aluminum-magnesium alloy filaments by cold drawing; V, continuously introducing the aluminum-magnesium alloy filaments into the palladium-ruthenium alloy pipe to obtain a blank piece; VI, swaging the blank piece to obtain a composite metal wire; and VII, performing cold drawing on the composite metal wire to obtain the palladium-ruthenium/aluminum-magnesium composite metal wire of a required size. The prepared palladium-ruthenium/aluminum-magnesium composite metal wire has high alloy reaction performance, and can be applied to a detonating cord of a detonator or an ignition device of an engine.

The invention discloses an energy containing metal bridged-film MEMS (Micro Electro Mechanical Systems) igniter and a preparation method thereof for a composite black body like energy concentrated structure. The energy containing metal bridged-film MEMS igniter sequentially comprises a silicon dioxide base layer, a chamber layer, a leak-proof silicon dioxide layer, a secondary radiation layer, an insulating secondary radiation layer, a lower electrode gold layer, a cupric oxide layer, an aluminum layer, an upper electrode gold layer from bottom to top; the silicon dioxide base layer, the chamber layer, the leak-proof silicon dioxide layer and the secondary radiation layer form into the black body like energy concentrated structure; the structure of a middle chamber of the chamber layer is in a hollow cone shape to concentrate energy, reduce integral device heat capacity and enable the secondary radiation layer to suspend; the cupric oxide layer and the aluminum layer form into the energy containing metal bridged-film. According to the energy containing metal bridged-film MEMS igniter, heat dissipation of the energy containing metal bridged-film MEMS igniter is reduced and ignition output is improved due to addition of the black body like energy concentrated structure; the heat accumulation time is shortened and accordingly the ignition delay time is reduced and the ignition instant performance is improved; concentration is beneficial due to the fact that micromachining is easy to achieve.

The invention discloses a pulse detonating combustion chamber and an air turbine rocket engine based on pulse detonating. The pulse detonating combustion chamber adopts an internal jet-flow tube ignition detonating way, and has better efficiency and feasibility in comparison with a transverse heat jet-flow ignition detonating method; internal heat jet-flow ignition is combined with a detonating way of mixing nano particles such as metal aluminum or titanium mixed in fuel oil, so that detonating waves within a relatively short distance and relatively short time can be achieved, and therefore, length of the detonating combustion chamber is shortened, working frequency of an engine is improved, and weight of the engine is reduced. Based on the pulse detonating combustion chamber, the air turbine rocket engine based on pulse detonating disclosed by the invention is improved in parameters such as thrust and specific pulse to certain extent in comparison with those of a conventional ART engine; while an overall pressure ratio of the engine is certain, PDC self-pressurization characteristic can reduce requirements, on pressurization ability of a gas compressor in a PD-ART engine, and grades of rotary parts can be reduced, engine weight is reduced, and therefore, a thrust-weight ratio is increased.

The invention discloses a ramjet with a function of high-speed pre-atomization of liquid aviation kerosene. The ramjet comprises a shunt cone, a gas inlet channel wall surface, a combustion chamber wall surface, an exhaust nozzle wall surface, an oil storage tank and an oil delivering pipe, wherein the shunt cone is connected with the oil storage tank through the oil delivering pipe; the gas inletchannel wall surface, the combustion chamber wall surface and the exhaust nozzle wall surface are connected in sequence; the shunt cone and the oil storage tank which serve as one part are arranged in a cavity formed by the gas inlet channel wall surface, the combustion chamber wall surface and the exhaust nozzle wall surface; a gas inlet channel is formed between the shunt cone and the gas inletchannel wall surface, a combustion chamber flow channel is formed between the shunt cone and the combustion chamber wall surface, an exhaust nozzle flow channel is formed between the shunt cone and the exhaust nozzle wall surface, and the gas inlet channel, the combustion chamber flow channel and the exhaust nozzle flow channel communicate in sequence; and a gas inlet hole is formed in the top ofthe shunt cone. The economy and safety of the ramjet are improved.

The invention relates to an aviation alternative fuel blending method for improving ignition performance of a heavy oil piston engine, which comprises the following steps: adding a component (1), a component (2), a component (3) or a combination thereof into an aviation fuel, the component (1) being selected from one or more of methylcyclopentane, methylcyclohexane and ethylcyclohexane; the component (2) is selected from one or more of propyl cyclopentane and propyl cyclohexane; and the component (3) is selected from one or more of C7-C10 paraffins. The invention also discloses an aviation fuel additive. The ignition performance of the aviation piston engine is remarkably improved, atomization, volatility, cetane number, ignition delay, ignition energy, heat value and ignition-extinguishing boundary are balanced, and meanwhile the working condition operation range is expanded.

Disclosed is a group of tertiary amine azides useful as hypergolic fuels for hypergolic bipropellant mixtures. The fuels provide higher density impulses than monomethyl hydrazine (MMH) but are less toxic and have lower vapor pressures that MMH. In addition, the fuels have shorter ignition delay times than dimethylaminoethylazide (DMAZ) and other potential reduced toxicity replacements for MMH.